1 | =head1 NAME
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2 |
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3 | perl581delta - what is new for perl v5.8.1
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4 |
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5 | =head1 DESCRIPTION
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6 |
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7 | This document describes differences between the 5.8.0 release and
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8 | the 5.8.1 release.
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9 |
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10 | If you are upgrading from an earlier release such as 5.6.1, first read
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11 | the L<perl58delta>, which describes differences between 5.6.0 and
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12 | 5.8.0.
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13 |
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14 | In case you are wondering about 5.6.1, it was bug-fix-wise rather
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15 | identical to the development release 5.7.1. Confused? This timeline
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16 | hopefully helps a bit: it lists the new major releases, their maintenance
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17 | releases, and the development releases.
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18 |
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19 | New Maintenance Development
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20 |
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21 | 5.6.0 2000-Mar-22
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22 | 5.7.0 2000-Sep-02
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23 | 5.6.1 2001-Apr-08
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24 | 5.7.1 2001-Apr-09
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25 | 5.7.2 2001-Jul-13
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26 | 5.7.3 2002-Mar-05
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27 | 5.8.0 2002-Jul-18
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28 | 5.8.1 2003-Sep-25
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29 |
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30 | =head1 Incompatible Changes
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31 |
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32 | =head2 Hash Randomisation
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33 |
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34 | Mainly due to security reasons, the "random ordering" of hashes
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35 | has been made even more random. Previously while the order of hash
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36 | elements from keys(), values(), and each() was essentially random,
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37 | it was still repeatable. Now, however, the order varies between
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38 | different runs of Perl.
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39 |
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40 | B<Perl has never guaranteed any ordering of the hash keys>, and the
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41 | ordering has already changed several times during the lifetime of
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42 | Perl 5. Also, the ordering of hash keys has always been, and
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43 | continues to be, affected by the insertion order.
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44 |
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45 | The added randomness may affect applications.
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46 |
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47 | One possible scenario is when output of an application has included
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48 | hash data. For example, if you have used the Data::Dumper module to
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49 | dump data into different files, and then compared the files to see
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50 | whether the data has changed, now you will have false positives since
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51 | the order in which hashes are dumped will vary. In general the cure
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52 | is to sort the keys (or the values); in particular for Data::Dumper to
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53 | use the C<Sortkeys> option. If some particular order is really
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54 | important, use tied hashes: for example the Tie::IxHash module
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55 | which by default preserves the order in which the hash elements
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56 | were added.
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57 |
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58 | More subtle problem is reliance on the order of "global destruction".
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59 | That is what happens at the end of execution: Perl destroys all data
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60 | structures, including user data. If your destructors (the DESTROY
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61 | subroutines) have assumed any particular ordering to the global
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62 | destruction, there might be problems ahead. For example, in a
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63 | destructor of one object you cannot assume that objects of any other
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64 | class are still available, unless you hold a reference to them.
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65 | If the environment variable PERL_DESTRUCT_LEVEL is set to a non-zero
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66 | value, or if Perl is exiting a spawned thread, it will also destruct
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67 | the ordinary references and the symbol tables that are no longer in use.
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68 | You can't call a class method or an ordinary function on a class that
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69 | has been collected that way.
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70 |
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71 | The hash randomisation is certain to reveal hidden assumptions about
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72 | some particular ordering of hash elements, and outright bugs: it
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73 | revealed a few bugs in the Perl core and core modules.
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74 |
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75 | To disable the hash randomisation in runtime, set the environment
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76 | variable PERL_HASH_SEED to 0 (zero) before running Perl (for more
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77 | information see L<perlrun/PERL_HASH_SEED>), or to disable the feature
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78 | completely in compile time, compile with C<-DNO_HASH_SEED> (see F<INSTALL>).
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79 |
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80 | See L<perlsec/"Algorithmic Complexity Attacks"> for the original
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81 | rationale behind this change.
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82 |
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83 | =head2 UTF-8 On Filehandles No Longer Activated By Locale
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84 |
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85 | In Perl 5.8.0 all filehandles, including the standard filehandles,
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86 | were implicitly set to be in Unicode UTF-8 if the locale settings
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87 | indicated the use of UTF-8. This feature caused too many problems,
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88 | so the feature was turned off and redesigned: see L</"Core Enhancements">.
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89 |
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90 | =head2 Single-number v-strings are no longer v-strings before "=>"
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91 |
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92 | The version strings or v-strings (see L<perldata/"Version Strings">)
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93 | feature introduced in Perl 5.6.0 has been a source of some confusion--
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94 | especially when the user did not want to use it, but Perl thought it
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95 | knew better. Especially troublesome has been the feature that before
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96 | a "=>" a version string (a "v" followed by digits) has been interpreted
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97 | as a v-string instead of a string literal. In other words:
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98 |
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99 | %h = ( v65 => 42 );
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100 |
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101 | has meant since Perl 5.6.0
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102 |
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103 | %h = ( 'A' => 42 );
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104 |
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105 | (at least in platforms of ASCII progeny) Perl 5.8.1 restores the
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106 | more natural interpretation
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107 |
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108 | %h = ( 'v65' => 42 );
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109 |
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110 | The multi-number v-strings like v65.66 and 65.66.67 still continue to
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111 | be v-strings in Perl 5.8.
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112 |
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113 | =head2 (Win32) The -C Switch Has Been Repurposed
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114 |
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115 | The -C switch has changed in an incompatible way. The old semantics
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116 | of this switch only made sense in Win32 and only in the "use utf8"
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117 | universe in 5.6.x releases, and do not make sense for the Unicode
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118 | implementation in 5.8.0. Since this switch could not have been used
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119 | by anyone, it has been repurposed. The behavior that this switch
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120 | enabled in 5.6.x releases may be supported in a transparent,
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121 | data-dependent fashion in a future release.
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122 |
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123 | For the new life of this switch, see L<"UTF-8 no longer default under
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124 | UTF-8 locales">, and L<perlrun/-C>.
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125 |
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126 | =head2 (Win32) The /d Switch Of cmd.exe
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127 |
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128 | Perl 5.8.1 uses the /d switch when running the cmd.exe shell
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129 | internally for system(), backticks, and when opening pipes to external
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130 | programs. The extra switch disables the execution of AutoRun commands
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131 | from the registry, which is generally considered undesirable when
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132 | running external programs. If you wish to retain compatibility with
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133 | the older behavior, set PERL5SHELL in your environment to C<cmd /x/c>.
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134 |
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135 | =head1 Core Enhancements
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136 |
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137 | =head2 UTF-8 no longer default under UTF-8 locales
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138 |
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139 | In Perl 5.8.0 many Unicode features were introduced. One of them
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140 | was found to be of more nuisance than benefit: the automagic
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141 | (and silent) "UTF-8-ification" of filehandles, including the
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142 | standard filehandles, if the user's locale settings indicated
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143 | use of UTF-8.
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144 |
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145 | For example, if you had C<en_US.UTF-8> as your locale, your STDIN and
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146 | STDOUT were automatically "UTF-8", in other words an implicit
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147 | binmode(..., ":utf8") was made. This meant that trying to print, say,
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148 | chr(0xff), ended up printing the bytes 0xc3 0xbf. Hardly what
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149 | you had in mind unless you were aware of this feature of Perl 5.8.0.
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150 | The problem is that the vast majority of people weren't: for example
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151 | in RedHat releases 8 and 9 the B<default> locale setting is UTF-8, so
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152 | all RedHat users got UTF-8 filehandles, whether they wanted it or not.
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153 | The pain was intensified by the Unicode implementation of Perl 5.8.0
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154 | (still) having nasty bugs, especially related to the use of s/// and
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155 | tr///. (Bugs that have been fixed in 5.8.1)
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156 |
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157 | Therefore a decision was made to backtrack the feature and change it
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158 | from implicit silent default to explicit conscious option. The new
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159 | Perl command line option C<-C> and its counterpart environment
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160 | variable PERL_UNICODE can now be used to control how Perl and Unicode
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161 | interact at interfaces like I/O and for example the command line
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162 | arguments. See L<perlrun/-C> and L<perlrun/PERL_UNICODE> for more
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163 | information.
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164 |
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165 | =head2 Unsafe signals again available
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166 |
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167 | In Perl 5.8.0 the so-called "safe signals" were introduced. This
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168 | means that Perl no longer handles signals immediately but instead
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169 | "between opcodes", when it is safe to do so. The earlier immediate
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170 | handling easily could corrupt the internal state of Perl, resulting
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171 | in mysterious crashes.
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172 |
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173 | However, the new safer model has its problems too. Because now an
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174 | opcode, a basic unit of Perl execution, is never interrupted but
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175 | instead let to run to completion, certain operations that can take a
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176 | long time now really do take a long time. For example, certain
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177 | network operations have their own blocking and timeout mechanisms, and
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178 | being able to interrupt them immediately would be nice.
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179 |
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180 | Therefore perl 5.8.1 introduces a "backdoor" to restore the pre-5.8.0
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181 | (pre-5.7.3, really) signal behaviour. Just set the environment variable
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182 | PERL_SIGNALS to C<unsafe>, and the old immediate (and unsafe)
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183 | signal handling behaviour returns. See L<perlrun/PERL_SIGNALS>
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184 | and L<perlipc/"Deferred Signals (Safe Signals)">.
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185 |
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186 | In completely unrelated news, you can now use safe signals with
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187 | POSIX::SigAction. See L<POSIX/POSIX::SigAction>.
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188 |
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189 | =head2 Tied Arrays with Negative Array Indices
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190 |
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191 | Formerly, the indices passed to C<FETCH>, C<STORE>, C<EXISTS>, and
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192 | C<DELETE> methods in tied array class were always non-negative. If
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193 | the actual argument was negative, Perl would call FETCHSIZE implicitly
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194 | and add the result to the index before passing the result to the tied
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195 | array method. This behaviour is now optional. If the tied array class
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196 | contains a package variable named C<$NEGATIVE_INDICES> which is set to
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197 | a true value, negative values will be passed to C<FETCH>, C<STORE>,
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198 | C<EXISTS>, and C<DELETE> unchanged.
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199 |
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200 | =head2 local ${$x}
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201 |
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202 | The syntaxes
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203 |
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204 | local ${$x}
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205 | local @{$x}
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206 | local %{$x}
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207 |
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208 | now do localise variables, given that the $x is a valid variable name.
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209 |
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210 | =head2 Unicode Character Database 4.0.0
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211 |
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212 | The copy of the Unicode Character Database included in Perl 5.8 has
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213 | been updated to 4.0.0 from 3.2.0. This means for example that the
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214 | Unicode character properties are as in Unicode 4.0.0.
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215 |
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216 | =head2 Deprecation Warnings
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217 |
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218 | There is one new feature deprecation. Perl 5.8.0 forgot to add
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219 | some deprecation warnings, these warnings have now been added.
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220 | Finally, a reminder of an impending feature removal.
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221 |
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222 | =head3 (Reminder) Pseudo-hashes are deprecated (really)
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223 |
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224 | Pseudo-hashes were deprecated in Perl 5.8.0 and will be removed in
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225 | Perl 5.10.0, see L<perl58delta> for details. Each attempt to access
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226 | pseudo-hashes will trigger the warning C<Pseudo-hashes are deprecated>.
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227 | If you really want to continue using pseudo-hashes but not to see the
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228 | deprecation warnings, use:
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229 |
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230 | no warnings 'deprecated';
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231 |
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232 | Or you can continue to use the L<fields> pragma, but please don't
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233 | expect the data structures to be pseudohashes any more.
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234 |
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235 | =head3 (Reminder) 5.005-style threads are deprecated (really)
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236 |
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237 | 5.005-style threads (activated by C<use Thread;>) were deprecated in
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238 | Perl 5.8.0 and will be removed after Perl 5.8, see L<perl58delta> for
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239 | details. Each 5.005-style thread creation will trigger the warning
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240 | C<5.005 threads are deprecated>. If you really want to continue
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241 | using the 5.005 threads but not to see the deprecation warnings, use:
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242 |
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243 | no warnings 'deprecated';
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244 |
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245 | =head3 (Reminder) The $* variable is deprecated (really)
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246 |
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247 | The C<$*> variable controlling multi-line matching has been deprecated
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248 | and will be removed after 5.8. The variable has been deprecated for a
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249 | long time, and a deprecation warning C<Use of $* is deprecated> is given,
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250 | now the variable will just finally be removed. The functionality has
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251 | been supplanted by the C</s> and C</m> modifiers on pattern matching.
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252 | If you really want to continue using the C<$*>-variable but not to see
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253 | the deprecation warnings, use:
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254 |
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255 | no warnings 'deprecated';
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256 |
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257 | =head2 Miscellaneous Enhancements
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258 |
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259 | C<map> in void context is no longer expensive. C<map> is now context
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260 | aware, and will not construct a list if called in void context.
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261 |
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262 | If a socket gets closed by the server while printing to it, the client
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263 | now gets a SIGPIPE. While this new feature was not planned, it fell
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264 | naturally out of PerlIO changes, and is to be considered an accidental
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265 | feature.
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266 |
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267 | PerlIO::get_layers(FH) returns the names of the PerlIO layers
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268 | active on a filehandle.
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269 |
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270 | PerlIO::via layers can now have an optional UTF8 method to
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271 | indicate whether the layer wants to "auto-:utf8" the stream.
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272 |
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273 | utf8::is_utf8() has been added as a quick way to test whether
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274 | a scalar is encoded internally in UTF-8 (Unicode).
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275 |
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276 | =head1 Modules and Pragmata
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277 |
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278 | =head2 Updated Modules And Pragmata
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279 |
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280 | The following modules and pragmata have been updated since Perl 5.8.0:
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281 |
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282 | =over 4
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283 |
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284 | =item base
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285 |
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286 | =item B::Bytecode
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287 |
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288 | In much better shape than it used to be. Still far from perfect, but
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289 | maybe worth a try.
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290 |
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291 | =item B::Concise
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292 |
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293 | =item B::Deparse
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294 |
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295 | =item Benchmark
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296 |
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297 | An optional feature, C<:hireswallclock>, now allows for high
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298 | resolution wall clock times (uses Time::HiRes).
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299 |
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300 | =item ByteLoader
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301 |
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302 | See B::Bytecode.
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303 |
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304 | =item bytes
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305 |
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306 | Now has bytes::substr.
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307 |
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308 | =item CGI
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309 |
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310 | =item charnames
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311 |
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312 | One can now have custom character name aliases.
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313 |
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314 | =item CPAN
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315 |
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316 | There is now a simple command line frontend to the CPAN.pm
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317 | module called F<cpan>.
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318 |
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319 | =item Data::Dumper
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320 |
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321 | A new option, Pair, allows choosing the separator between hash keys
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322 | and values.
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323 |
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324 | =item DB_File
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325 |
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326 | =item Devel::PPPort
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327 |
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328 | =item Digest::MD5
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329 |
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330 | =item Encode
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331 |
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332 | Significant updates on the encoding pragma functionality
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333 | (tr/// and the DATA filehandle, formats).
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334 |
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335 | If a filehandle has been marked as to have an encoding, unmappable
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336 | characters are detected already during input, not later (when the
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337 | corrupted data is being used).
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338 |
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339 | The ISO 8859-6 conversion table has been corrected (the 0x30..0x39
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340 | erroneously mapped to U+0660..U+0669, instead of U+0030..U+0039). The
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341 | GSM 03.38 conversion did not handle escape sequences correctly. The
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342 | UTF-7 encoding has been added (making Encode feature-complete with
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343 | Unicode::String).
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344 |
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345 | =item fields
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346 |
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347 | =item libnet
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348 |
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349 | =item Math::BigInt
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350 |
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351 | A lot of bugs have been fixed since v1.60, the version included in Perl
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352 | v5.8.0. Especially noteworthy are the bug in Calc that caused div and mod to
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353 | fail for some large values, and the fixes to the handling of bad inputs.
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354 |
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355 | Some new features were added, e.g. the broot() method, you can now pass
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356 | parameters to config() to change some settings at runtime, and it is now
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357 | possible to trap the creation of NaN and infinity.
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358 |
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359 | As usual, some optimizations took place and made the math overall a tad
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360 | faster. In some cases, quite a lot faster, actually. Especially alternative
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361 | libraries like Math::BigInt::GMP benefit from this. In addition, a lot of the
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362 | quite clunky routines like fsqrt() and flog() are now much much faster.
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363 |
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364 | =item MIME::Base64
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365 |
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366 | =item NEXT
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367 |
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368 | Diamond inheritance now works.
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369 |
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370 | =item Net::Ping
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371 |
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372 | =item PerlIO::scalar
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373 |
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374 | Reading from non-string scalars (like the special variables, see
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375 | L<perlvar>) now works.
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376 |
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377 | =item podlators
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378 |
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379 | =item Pod::LaTeX
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380 |
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381 | =item PodParsers
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382 |
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383 | =item Pod::Perldoc
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384 |
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385 | Complete rewrite. As a side-effect, no longer refuses to startup when
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386 | run by root.
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387 |
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388 | =item Scalar::Util
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389 |
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390 | New utilities: refaddr, isvstring, looks_like_number, set_prototype.
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391 |
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392 | =item Storable
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393 |
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394 | Can now store code references (via B::Deparse, so not foolproof).
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395 |
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396 | =item strict
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397 |
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398 | Earlier versions of the strict pragma did not check the parameters
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399 | implicitly passed to its "import" (use) and "unimport" (no) routine.
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400 | This caused the false idiom such as:
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401 |
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402 | use strict qw(@ISA);
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403 | @ISA = qw(Foo);
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404 |
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405 | This however (probably) raised the false expectation that the strict
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406 | refs, vars and subs were being enforced (and that @ISA was somehow
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407 | "declared"). But the strict refs, vars, and subs are B<not> enforced
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408 | when using this false idiom.
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409 |
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410 | Starting from Perl 5.8.1, the above B<will> cause an error to be
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411 | raised. This may cause programs which used to execute seemingly
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412 | correctly without warnings and errors to fail when run under 5.8.1.
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413 | This happens because
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414 |
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415 | use strict qw(@ISA);
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416 |
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417 | will now fail with the error:
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418 |
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419 | Unknown 'strict' tag(s) '@ISA'
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420 |
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421 | The remedy to this problem is to replace this code with the correct idiom:
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422 |
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423 | use strict;
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424 | use vars qw(@ISA);
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425 | @ISA = qw(Foo);
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426 |
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427 | =item Term::ANSIcolor
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428 |
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429 | =item Test::Harness
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430 |
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431 | Now much more picky about extra or missing output from test scripts.
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432 |
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433 | =item Test::More
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434 |
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435 | =item Test::Simple
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436 |
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437 | =item Text::Balanced
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438 |
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439 | =item Time::HiRes
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440 |
|
---|
441 | Use of nanosleep(), if available, allows mixing subsecond sleeps with
|
---|
442 | alarms.
|
---|
443 |
|
---|
444 | =item threads
|
---|
445 |
|
---|
446 | Several fixes, for example for join() problems and memory
|
---|
447 | leaks. In some platforms (like Linux) that use glibc the minimum memory
|
---|
448 | footprint of one ithread has been reduced by several hundred kilobytes.
|
---|
449 |
|
---|
450 | =item threads::shared
|
---|
451 |
|
---|
452 | Many memory leaks have been fixed.
|
---|
453 |
|
---|
454 | =item Unicode::Collate
|
---|
455 |
|
---|
456 | =item Unicode::Normalize
|
---|
457 |
|
---|
458 | =item Win32::GetFolderPath
|
---|
459 |
|
---|
460 | =item Win32::GetOSVersion
|
---|
461 |
|
---|
462 | Now returns extra information.
|
---|
463 |
|
---|
464 | =back
|
---|
465 |
|
---|
466 | =head1 Utility Changes
|
---|
467 |
|
---|
468 | The C<h2xs> utility now produces a more modern layout:
|
---|
469 | F<Foo-Bar/lib/Foo/Bar.pm> instead of F<Foo/Bar/Bar.pm>.
|
---|
470 | Also, the boilerplate test is now called F<t/Foo-Bar.t>
|
---|
471 | instead of F<t/1.t>.
|
---|
472 |
|
---|
473 | The Perl debugger (F<lib/perl5db.pl>) has now been extensively
|
---|
474 | documented and bugs found while documenting have been fixed.
|
---|
475 |
|
---|
476 | C<perldoc> has been rewritten from scratch to be more robust and
|
---|
477 | featureful.
|
---|
478 |
|
---|
479 | C<perlcc -B> works now at least somewhat better, while C<perlcc -c>
|
---|
480 | is rather more broken. (The Perl compiler suite as a whole continues
|
---|
481 | to be experimental.)
|
---|
482 |
|
---|
483 | =head1 New Documentation
|
---|
484 |
|
---|
485 | perl573delta has been added to list the differences between the
|
---|
486 | (now quite obsolete) development releases 5.7.2 and 5.7.3.
|
---|
487 |
|
---|
488 | perl58delta has been added: it is the perldelta of 5.8.0, detailing
|
---|
489 | the differences between 5.6.0 and 5.8.0.
|
---|
490 |
|
---|
491 | perlartistic has been added: it is the Artistic License in pod format,
|
---|
492 | making it easier for modules to refer to it.
|
---|
493 |
|
---|
494 | perlcheat has been added: it is a Perl cheat sheet.
|
---|
495 |
|
---|
496 | perlgpl has been added: it is the GNU General Public License in pod
|
---|
497 | format, making it easier for modules to refer to it.
|
---|
498 |
|
---|
499 | perlmacosx has been added to tell about the installation and use
|
---|
500 | of Perl in Mac OS X.
|
---|
501 |
|
---|
502 | perlos400 has been added to tell about the installation and use
|
---|
503 | of Perl in OS/400 PASE.
|
---|
504 |
|
---|
505 | perlreref has been added: it is a regular expressions quick reference.
|
---|
506 |
|
---|
507 | =head1 Installation and Configuration Improvements
|
---|
508 |
|
---|
509 | The UNIX standard Perl location, F</usr/bin/perl>, is no longer
|
---|
510 | overwritten by default if it exists. This change was very prudent
|
---|
511 | because so many UNIX vendors already provide a F</usr/bin/perl>,
|
---|
512 | but simultaneously many system utilities may depend on that
|
---|
513 | exact version of Perl, so better not to overwrite it.
|
---|
514 |
|
---|
515 | One can now specify installation directories for site and vendor man
|
---|
516 | and HTML pages, and site and vendor scripts. See F<INSTALL>.
|
---|
517 |
|
---|
518 | One can now specify a destination directory for Perl installation
|
---|
519 | by specifying the DESTDIR variable for C<make install>. (This feature
|
---|
520 | is slightly different from the previous C<Configure -Dinstallprefix=...>.)
|
---|
521 | See F<INSTALL>.
|
---|
522 |
|
---|
523 | gcc versions 3.x introduced a new warning that caused a lot of noise
|
---|
524 | during Perl compilation: C<gcc -Ialreadyknowndirectory (warning:
|
---|
525 | changing search order)>. This warning has now been avoided by
|
---|
526 | Configure weeding out such directories before the compilation.
|
---|
527 |
|
---|
528 | One can now build subsets of Perl core modules by using the
|
---|
529 | Configure flags C<-Dnoextensions=...> and C<-Donlyextensions=...>,
|
---|
530 | see F<INSTALL>.
|
---|
531 |
|
---|
532 | =head2 Platform-specific enhancements
|
---|
533 |
|
---|
534 | In Cygwin Perl can now be built with threads (C<Configure -Duseithreads>).
|
---|
535 | This works with both Cygwin 1.3.22 and Cygwin 1.5.3.
|
---|
536 |
|
---|
537 | In newer FreeBSD releases Perl 5.8.0 compilation failed because of
|
---|
538 | trying to use F<malloc.h>, which in FreeBSD is just a dummy file, and
|
---|
539 | a fatal error to even try to use. Now F<malloc.h> is not used.
|
---|
540 |
|
---|
541 | Perl is now known to build also in Hitachi HI-UXMPP.
|
---|
542 |
|
---|
543 | Perl is now known to build again in LynxOS.
|
---|
544 |
|
---|
545 | Mac OS X now installs with Perl version number embedded in
|
---|
546 | installation directory names for easier upgrading of user-compiled
|
---|
547 | Perl, and the installation directories in general are more standard.
|
---|
548 | In other words, the default installation no longer breaks the
|
---|
549 | Apple-provided Perl. On the other hand, with C<Configure -Dprefix=/usr>
|
---|
550 | you can now really replace the Apple-supplied Perl (B<please be careful>).
|
---|
551 |
|
---|
552 | Mac OS X now builds Perl statically by default. This change was done
|
---|
553 | mainly for faster startup times. The Apple-provided Perl is still
|
---|
554 | dynamically linked and shared, and you can enable the sharedness for
|
---|
555 | your own Perl builds by C<Configure -Duseshrplib>.
|
---|
556 |
|
---|
557 | Perl has been ported to IBM's OS/400 PASE environment. The best way
|
---|
558 | to build a Perl for PASE is to use an AIX host as a cross-compilation
|
---|
559 | environment. See README.os400.
|
---|
560 |
|
---|
561 | Yet another cross-compilation option has been added: now Perl builds
|
---|
562 | on OpenZaurus, an Linux distribution based on Mandrake + Embedix for
|
---|
563 | the Sharp Zaurus PDA. See the Cross/README file.
|
---|
564 |
|
---|
565 | Tru64 when using gcc 3 drops the optimisation for F<toke.c> to C<-O2>
|
---|
566 | because of gigantic memory use with the default C<-O3>.
|
---|
567 |
|
---|
568 | Tru64 can now build Perl with the newer Berkeley DBs.
|
---|
569 |
|
---|
570 | Building Perl on WinCE has been much enhanced, see F<README.ce>
|
---|
571 | and F<README.perlce>.
|
---|
572 |
|
---|
573 | =head1 Selected Bug Fixes
|
---|
574 |
|
---|
575 | =head2 Closures, eval and lexicals
|
---|
576 |
|
---|
577 | There have been many fixes in the area of anonymous subs, lexicals and
|
---|
578 | closures. Although this means that Perl is now more "correct", it is
|
---|
579 | possible that some existing code will break that happens to rely on
|
---|
580 | the faulty behaviour. In practice this is unlikely unless your code
|
---|
581 | contains a very complex nesting of anonymous subs, evals and lexicals.
|
---|
582 |
|
---|
583 | =head2 Generic fixes
|
---|
584 |
|
---|
585 | If an input filehandle is marked C<:utf8> and Perl sees illegal UTF-8
|
---|
586 | coming in when doing C<< <FH> >>, if warnings are enabled a warning is
|
---|
587 | immediately given - instead of being silent about it and Perl being
|
---|
588 | unhappy about the broken data later. (The C<:encoding(utf8)> layer
|
---|
589 | also works the same way.)
|
---|
590 |
|
---|
591 | binmode(SOCKET, ":utf8") only worked on the input side, not on the
|
---|
592 | output side of the socket. Now it works both ways.
|
---|
593 |
|
---|
594 | For threaded Perls certain system database functions like getpwent()
|
---|
595 | and getgrent() now grow their result buffer dynamically, instead of
|
---|
596 | failing. This means that at sites with lots of users and groups the
|
---|
597 | functions no longer fail by returning only partial results.
|
---|
598 |
|
---|
599 | Perl 5.8.0 had accidentally broken the capability for users
|
---|
600 | to define their own uppercase<->lowercase Unicode mappings
|
---|
601 | (as advertised by the Camel). This feature has been fixed and
|
---|
602 | is also documented better.
|
---|
603 |
|
---|
604 | In 5.8.0 this
|
---|
605 |
|
---|
606 | $some_unicode .= <FH>;
|
---|
607 |
|
---|
608 | didn't work correctly but instead corrupted the data. This has now
|
---|
609 | been fixed.
|
---|
610 |
|
---|
611 | Tied methods like FETCH etc. may now safely access tied values, i.e.
|
---|
612 | resulting in a recursive call to FETCH etc. Remember to break the
|
---|
613 | recursion, though.
|
---|
614 |
|
---|
615 | At startup Perl blocks the SIGFPE signal away since there isn't much
|
---|
616 | Perl can do about it. Previously this blocking was in effect also for
|
---|
617 | programs executed from within Perl. Now Perl restores the original
|
---|
618 | SIGFPE handling routine, whatever it was, before running external
|
---|
619 | programs.
|
---|
620 |
|
---|
621 | Linenumbers in Perl scripts may now be greater than 65536, or 2**16.
|
---|
622 | (Perl scripts have always been able to be larger than that, it's just
|
---|
623 | that the linenumber for reported errors and warnings have "wrapped
|
---|
624 | around".) While scripts that large usually indicate a need to rethink
|
---|
625 | your code a bit, such Perl scripts do exist, for example as results
|
---|
626 | from generated code. Now linenumbers can go all the way to
|
---|
627 | 4294967296, or 2**32.
|
---|
628 |
|
---|
629 | =head2 Platform-specific fixes
|
---|
630 |
|
---|
631 | Linux
|
---|
632 |
|
---|
633 | =over 4
|
---|
634 |
|
---|
635 | =item *
|
---|
636 |
|
---|
637 | Setting $0 works again (with certain limitations that
|
---|
638 | Perl cannot do much about: see L<perlvar/$0>)
|
---|
639 |
|
---|
640 | =back
|
---|
641 |
|
---|
642 | HP-UX
|
---|
643 |
|
---|
644 | =over 4
|
---|
645 |
|
---|
646 | =item *
|
---|
647 |
|
---|
648 | Setting $0 now works.
|
---|
649 |
|
---|
650 | =back
|
---|
651 |
|
---|
652 | VMS
|
---|
653 |
|
---|
654 | =over 4
|
---|
655 |
|
---|
656 | =item *
|
---|
657 |
|
---|
658 | Configuration now tests for the presence of C<poll()>, and IO::Poll
|
---|
659 | now uses the vendor-supplied function if detected.
|
---|
660 |
|
---|
661 | =item *
|
---|
662 |
|
---|
663 | A rare access violation at Perl start-up could occur if the Perl image was
|
---|
664 | installed with privileges or if there was an identifier with the
|
---|
665 | subsystem attribute set in the process's rightslist. Either of these
|
---|
666 | circumstances triggered tainting code that contained a pointer bug.
|
---|
667 | The faulty pointer arithmetic has been fixed.
|
---|
668 |
|
---|
669 | =item *
|
---|
670 |
|
---|
671 | The length limit on values (not keys) in the %ENV hash has been raised
|
---|
672 | from 255 bytes to 32640 bytes (except when the PERL_ENV_TABLES setting
|
---|
673 | overrides the default use of logical names for %ENV). If it is
|
---|
674 | necessary to access these long values from outside Perl, be aware that
|
---|
675 | they are implemented using search list logical names that store the
|
---|
676 | value in pieces, each 255-byte piece (up to 128 of them) being an
|
---|
677 | element in the search list. When doing a lookup in %ENV from within
|
---|
678 | Perl, the elements are combined into a single value. The existing
|
---|
679 | VMS-specific ability to access individual elements of a search list
|
---|
680 | logical name via the $ENV{'foo;N'} syntax (where N is the search list
|
---|
681 | index) is unimpaired.
|
---|
682 |
|
---|
683 | =item *
|
---|
684 |
|
---|
685 | The piping implementation now uses local rather than global DCL
|
---|
686 | symbols for inter-process communication.
|
---|
687 |
|
---|
688 | =item *
|
---|
689 |
|
---|
690 | File::Find could become confused when navigating to a relative
|
---|
691 | directory whose name collided with a logical name. This problem has
|
---|
692 | been corrected by adding directory syntax to relative path names, thus
|
---|
693 | preventing logical name translation.
|
---|
694 |
|
---|
695 | =back
|
---|
696 |
|
---|
697 | Win32
|
---|
698 |
|
---|
699 | =over 4
|
---|
700 |
|
---|
701 | =item *
|
---|
702 |
|
---|
703 | A memory leak in the fork() emulation has been fixed.
|
---|
704 |
|
---|
705 | =item *
|
---|
706 |
|
---|
707 | The return value of the ioctl() built-in function was accidentally
|
---|
708 | broken in 5.8.0. This has been corrected.
|
---|
709 |
|
---|
710 | =item *
|
---|
711 |
|
---|
712 | The internal message loop executed by perl during blocking operations
|
---|
713 | sometimes interfered with messages that were external to Perl.
|
---|
714 | This often resulted in blocking operations terminating prematurely or
|
---|
715 | returning incorrect results, when Perl was executing under environments
|
---|
716 | that could generate Windows messages. This has been corrected.
|
---|
717 |
|
---|
718 | =item *
|
---|
719 |
|
---|
720 | Pipes and sockets are now automatically in binary mode.
|
---|
721 |
|
---|
722 | =item *
|
---|
723 |
|
---|
724 | The four-argument form of select() did not preserve $! (errno) properly
|
---|
725 | when there were errors in the underlying call. This is now fixed.
|
---|
726 |
|
---|
727 | =item *
|
---|
728 |
|
---|
729 | The "CR CR LF" problem of has been fixed, binmode(FH, ":crlf")
|
---|
730 | is now effectively a no-op.
|
---|
731 |
|
---|
732 | =back
|
---|
733 |
|
---|
734 | =head1 New or Changed Diagnostics
|
---|
735 |
|
---|
736 | All the warnings related to pack() and unpack() were made more
|
---|
737 | informative and consistent.
|
---|
738 |
|
---|
739 | =head2 Changed "A thread exited while %d threads were running"
|
---|
740 |
|
---|
741 | The old version
|
---|
742 |
|
---|
743 | A thread exited while %d other threads were still running
|
---|
744 |
|
---|
745 | was misleading because the "other" included also the thread giving
|
---|
746 | the warning.
|
---|
747 |
|
---|
748 | =head2 Removed "Attempt to clear a restricted hash"
|
---|
749 |
|
---|
750 | It is not illegal to clear a restricted hash, so the warning
|
---|
751 | was removed.
|
---|
752 |
|
---|
753 | =head2 New "Illegal declaration of anonymous subroutine"
|
---|
754 |
|
---|
755 | You must specify the block of code for C<sub>.
|
---|
756 |
|
---|
757 | =head2 Changed "Invalid range "%s" in transliteration operator"
|
---|
758 |
|
---|
759 | The old version
|
---|
760 |
|
---|
761 | Invalid [] range "%s" in transliteration operator
|
---|
762 |
|
---|
763 | was simply wrong because there are no "[] ranges" in tr///.
|
---|
764 |
|
---|
765 | =head2 New "Missing control char name in \c"
|
---|
766 |
|
---|
767 | Self-explanatory.
|
---|
768 |
|
---|
769 | =head2 New "Newline in left-justified string for %s"
|
---|
770 |
|
---|
771 | The padding spaces would appear after the newline, which is
|
---|
772 | probably not what you had in mind.
|
---|
773 |
|
---|
774 | =head2 New "Possible precedence problem on bitwise %c operator"
|
---|
775 |
|
---|
776 | If you think this
|
---|
777 |
|
---|
778 | $x & $y == 0
|
---|
779 |
|
---|
780 | tests whether the bitwise AND of $x and $y is zero,
|
---|
781 | you will like this warning.
|
---|
782 |
|
---|
783 | =head2 New "Pseudo-hashes are deprecated"
|
---|
784 |
|
---|
785 | This warning should have been already in 5.8.0, since they are.
|
---|
786 |
|
---|
787 | =head2 New "read() on %s filehandle %s"
|
---|
788 |
|
---|
789 | You cannot read() (or sysread()) from a closed or unopened filehandle.
|
---|
790 |
|
---|
791 | =head2 New "5.005 threads are deprecated"
|
---|
792 |
|
---|
793 | This warning should have been already in 5.8.0, since they are.
|
---|
794 |
|
---|
795 | =head2 New "Tied variable freed while still in use"
|
---|
796 |
|
---|
797 | Something pulled the plug on a live tied variable, Perl plays
|
---|
798 | safe by bailing out.
|
---|
799 |
|
---|
800 | =head2 New "To%s: illegal mapping '%s'"
|
---|
801 |
|
---|
802 | An illegal user-defined Unicode casemapping was specified.
|
---|
803 |
|
---|
804 | =head2 New "Use of freed value in iteration"
|
---|
805 |
|
---|
806 | Something modified the values being iterated over. This is not good.
|
---|
807 |
|
---|
808 | =head1 Changed Internals
|
---|
809 |
|
---|
810 | These news matter to you only if you either write XS code or like to
|
---|
811 | know about or hack Perl internals (using Devel::Peek or any of the
|
---|
812 | C<B::> modules counts), or like to run Perl with the C<-D> option.
|
---|
813 |
|
---|
814 | The embedding examples of L<perlembed> have been reviewed to be
|
---|
815 | uptodate and consistent: for example, the correct use of
|
---|
816 | PERL_SYS_INIT3() and PERL_SYS_TERM().
|
---|
817 |
|
---|
818 | Extensive reworking of the pad code (the code responsible
|
---|
819 | for lexical variables) has been conducted by Dave Mitchell.
|
---|
820 |
|
---|
821 | Extensive work on the v-strings by John Peacock.
|
---|
822 |
|
---|
823 | UTF-8 length and position cache: to speed up the handling of Unicode
|
---|
824 | (UTF-8) scalars, a cache was introduced. Potential problems exist if
|
---|
825 | an extension bypasses the official APIs and directly modifies the PV
|
---|
826 | of an SV: the UTF-8 cache does not get cleared as it should.
|
---|
827 |
|
---|
828 | APIs obsoleted in Perl 5.8.0, like sv_2pv, sv_catpvn, sv_catsv,
|
---|
829 | sv_setsv, are again available.
|
---|
830 |
|
---|
831 | Certain Perl core C APIs like cxinc and regatom are no longer
|
---|
832 | available at all to code outside the Perl core of the Perl core
|
---|
833 | extensions. This is intentional. They never should have been
|
---|
834 | available with the shorter names, and if you application depends on
|
---|
835 | them, you should (be ashamed and) contact perl5-porters to discuss
|
---|
836 | what are the proper APIs.
|
---|
837 |
|
---|
838 | Certain Perl core C APIs like C<Perl_list> are no longer available
|
---|
839 | without their C<Perl_> prefix. If your XS module stops working
|
---|
840 | because some functions cannot be found, in many cases a simple fix is
|
---|
841 | to add the C<Perl_> prefix to the function and the thread context
|
---|
842 | C<aTHX_> as the first argument of the function call. This is also how
|
---|
843 | it should always have been done: letting the Perl_-less forms to leak
|
---|
844 | from the core was an accident. For cleaner embedding you can also
|
---|
845 | force this for all APIs by defining at compile time the cpp define
|
---|
846 | PERL_NO_SHORT_NAMES.
|
---|
847 |
|
---|
848 | Perl_save_bool() has been added.
|
---|
849 |
|
---|
850 | Regexp objects (those created with C<qr>) now have S-magic rather than
|
---|
851 | R-magic. This fixed regexps of the form /...(??{...;$x})/ to no
|
---|
852 | longer ignore changes made to $x. The S-magic avoids dropping
|
---|
853 | the caching optimization and making (??{...}) constructs obscenely
|
---|
854 | slow (and consequently useless). See also L<perlguts/"Magic Variables">.
|
---|
855 | Regexp::Copy was affected by this change.
|
---|
856 |
|
---|
857 | The Perl internal debugging macros DEBUG() and DEB() have been renamed
|
---|
858 | to PERL_DEBUG() and PERL_DEB() to avoid namespace conflicts.
|
---|
859 |
|
---|
860 | C<-DL> removed (the leaktest had been broken and unsupported for years,
|
---|
861 | use alternative debugging mallocs or tools like valgrind and Purify).
|
---|
862 |
|
---|
863 | Verbose modifier C<v> added for C<-DXv> and C<-Dsv>, see L<perlrun>.
|
---|
864 |
|
---|
865 | =head1 New Tests
|
---|
866 |
|
---|
867 | In Perl 5.8.0 there were about 69000 separate tests in about 700 test files,
|
---|
868 | in Perl 5.8.1 there are about 77000 separate tests in about 780 test files.
|
---|
869 | The exact numbers depend on the Perl configuration and on the operating
|
---|
870 | system platform.
|
---|
871 |
|
---|
872 | =head1 Known Problems
|
---|
873 |
|
---|
874 | The hash randomisation mentioned in L</Incompatible Changes> is definitely
|
---|
875 | problematic: it will wake dormant bugs and shake out bad assumptions.
|
---|
876 |
|
---|
877 | If you want to use mod_perl 2.x with Perl 5.8.1, you will need
|
---|
878 | mod_perl-1.99_10 or higher. Earlier versions of mod_perl 2.x
|
---|
879 | do not work with the randomised hashes. (mod_perl 1.x works fine.)
|
---|
880 | You will also need Apache::Test 1.04 or higher.
|
---|
881 |
|
---|
882 | Many of the rarer platforms that worked 100% or pretty close to it
|
---|
883 | with perl 5.8.0 have been left a little bit untended since their
|
---|
884 | maintainers have been otherwise busy lately, and therefore there will
|
---|
885 | be more failures on those platforms. Such platforms include Mac OS
|
---|
886 | Classic, IBM z/OS (and other EBCDIC platforms), and NetWare. The most
|
---|
887 | common Perl platforms (Unix and Unix-like, Microsoft platforms, and
|
---|
888 | VMS) have large enough testing and expert population that they are
|
---|
889 | doing well.
|
---|
890 |
|
---|
891 | =head2 Tied hashes in scalar context
|
---|
892 |
|
---|
893 | Tied hashes do not currently return anything useful in scalar context,
|
---|
894 | for example when used as boolean tests:
|
---|
895 |
|
---|
896 | if (%tied_hash) { ... }
|
---|
897 |
|
---|
898 | The current nonsensical behaviour is always to return false,
|
---|
899 | regardless of whether the hash is empty or has elements.
|
---|
900 |
|
---|
901 | The root cause is that there is no interface for the implementors of
|
---|
902 | tied hashes to implement the behaviour of a hash in scalar context.
|
---|
903 |
|
---|
904 | =head2 Net::Ping 450_service and 510_ping_udp failures
|
---|
905 |
|
---|
906 | The subtests 9 and 18 of lib/Net/Ping/t/450_service.t, and the
|
---|
907 | subtest 2 of lib/Net/Ping/t/510_ping_udp.t might fail if you have
|
---|
908 | an unusual networking setup. For example in the latter case the
|
---|
909 | test is trying to send a UDP ping to the IP address 127.0.0.1.
|
---|
910 |
|
---|
911 | =head2 B::C
|
---|
912 |
|
---|
913 | The C-generating compiler backend B::C (the frontend being
|
---|
914 | C<perlcc -c>) is even more broken than it used to be because of
|
---|
915 | the extensive lexical variable changes. (The good news is that
|
---|
916 | B::Bytecode and ByteLoader are better than they used to be.)
|
---|
917 |
|
---|
918 | =head1 Platform Specific Problems
|
---|
919 |
|
---|
920 | =head2 EBCDIC Platforms
|
---|
921 |
|
---|
922 | IBM z/OS and other EBCDIC platforms continue to be problematic
|
---|
923 | regarding Unicode support. Many Unicode tests are skipped when
|
---|
924 | they really should be fixed.
|
---|
925 |
|
---|
926 | =head2 Cygwin 1.5 problems
|
---|
927 |
|
---|
928 | In Cygwin 1.5 the F<io/tell> and F<op/sysio> tests have failures for
|
---|
929 | some yet unknown reason. In 1.5.5 the threads tests stress_cv,
|
---|
930 | stress_re, and stress_string are failing unless the environment
|
---|
931 | variable PERLIO is set to "perlio" (which makes also the io/tell
|
---|
932 | failure go away).
|
---|
933 |
|
---|
934 | Perl 5.8.1 does build and work well with Cygwin 1.3: with (uname -a)
|
---|
935 | C<CYGWIN_NT-5.0 ... 1.3.22(0.78/3/2) 2003-03-18 09:20 i686 ...>
|
---|
936 | a 100% "make test" was achieved with C<Configure -des -Duseithreads>.
|
---|
937 |
|
---|
938 | =head2 HP-UX: HP cc warnings about sendfile and sendpath
|
---|
939 |
|
---|
940 | With certain HP C compiler releases (e.g. B.11.11.02) you will
|
---|
941 | get many warnings like this (lines wrapped for easier reading):
|
---|
942 |
|
---|
943 | cc: "/usr/include/sys/socket.h", line 504: warning 562:
|
---|
944 | Redeclaration of "sendfile" with a different storage class specifier:
|
---|
945 | "sendfile" will have internal linkage.
|
---|
946 | cc: "/usr/include/sys/socket.h", line 505: warning 562:
|
---|
947 | Redeclaration of "sendpath" with a different storage class specifier:
|
---|
948 | "sendpath" will have internal linkage.
|
---|
949 |
|
---|
950 | The warnings show up both during the build of Perl and during certain
|
---|
951 | lib/ExtUtils tests that invoke the C compiler. The warning, however,
|
---|
952 | is not serious and can be ignored.
|
---|
953 |
|
---|
954 | =head2 IRIX: t/uni/tr_7jis.t falsely failing
|
---|
955 |
|
---|
956 | The test t/uni/tr_7jis.t is known to report failure under 'make test'
|
---|
957 | or the test harness with certain releases of IRIX (at least IRIX 6.5
|
---|
958 | and MIPSpro Compilers Version 7.3.1.1m), but if run manually the test
|
---|
959 | fully passes.
|
---|
960 |
|
---|
961 | =head2 Mac OS X: no usemymalloc
|
---|
962 |
|
---|
963 | The Perl malloc (C<-Dusemymalloc>) does not work at all in Mac OS X.
|
---|
964 | This is not that serious, though, since the native malloc works just
|
---|
965 | fine.
|
---|
966 |
|
---|
967 | =head2 Tru64: No threaded builds with GNU cc (gcc)
|
---|
968 |
|
---|
969 | In the latest Tru64 releases (e.g. v5.1B or later) gcc cannot be used
|
---|
970 | to compile a threaded Perl (-Duseithreads) because the system
|
---|
971 | C<< <pthread.h> >> file doesn't know about gcc.
|
---|
972 |
|
---|
973 | =head2 Win32: sysopen, sysread, syswrite
|
---|
974 |
|
---|
975 | As of the 5.8.0 release, sysopen()/sysread()/syswrite() do not behave
|
---|
976 | like they used to in 5.6.1 and earlier with respect to "text" mode.
|
---|
977 | These built-ins now always operate in "binary" mode (even if sysopen()
|
---|
978 | was passed the O_TEXT flag, or if binmode() was used on the file
|
---|
979 | handle). Note that this issue should only make a difference for disk
|
---|
980 | files, as sockets and pipes have always been in "binary" mode in the
|
---|
981 | Windows port. As this behavior is currently considered a bug,
|
---|
982 | compatible behavior may be re-introduced in a future release. Until
|
---|
983 | then, the use of sysopen(), sysread() and syswrite() is not supported
|
---|
984 | for "text" mode operations.
|
---|
985 |
|
---|
986 | =head1 Future Directions
|
---|
987 |
|
---|
988 | The following things B<might> happen in future. The first publicly
|
---|
989 | available releases having these characteristics will be the developer
|
---|
990 | releases Perl 5.9.x, culminating in the Perl 5.10.0 release. These
|
---|
991 | are our best guesses at the moment: we reserve the right to rethink.
|
---|
992 |
|
---|
993 | =over 4
|
---|
994 |
|
---|
995 | =item *
|
---|
996 |
|
---|
997 | PerlIO will become The Default. Currently (in Perl 5.8.x) the stdio
|
---|
998 | library is still used if Perl thinks it can use certain tricks to
|
---|
999 | make stdio go B<really> fast. For future releases our goal is to
|
---|
1000 | make PerlIO go even faster.
|
---|
1001 |
|
---|
1002 | =item *
|
---|
1003 |
|
---|
1004 | A new feature called I<assertions> will be available. This means that
|
---|
1005 | one can have code called assertions sprinkled in the code: usually
|
---|
1006 | they are optimised away, but they can be enabled with the C<-A> option.
|
---|
1007 |
|
---|
1008 | =item *
|
---|
1009 |
|
---|
1010 | A new operator C<//> (defined-or) will be available. This means that
|
---|
1011 | one will be able to say
|
---|
1012 |
|
---|
1013 | $a // $b
|
---|
1014 |
|
---|
1015 | instead of
|
---|
1016 |
|
---|
1017 | defined $a ? $a : $b
|
---|
1018 |
|
---|
1019 | and
|
---|
1020 |
|
---|
1021 | $c //= $d;
|
---|
1022 |
|
---|
1023 | instead of
|
---|
1024 |
|
---|
1025 | $c = $d unless defined $c;
|
---|
1026 |
|
---|
1027 | The operator will have the same precedence and associativity as C<||>.
|
---|
1028 | A source code patch against the Perl 5.8.1 sources will be available
|
---|
1029 | in CPAN as F<authors/id/H/HM/HMBRAND/dor-5.8.1.diff>.
|
---|
1030 |
|
---|
1031 | =item *
|
---|
1032 |
|
---|
1033 | C<unpack()> will default to unpacking the C<$_>.
|
---|
1034 |
|
---|
1035 | =item *
|
---|
1036 |
|
---|
1037 | Various Copy-On-Write techniques will be investigated in hopes
|
---|
1038 | of speeding up Perl.
|
---|
1039 |
|
---|
1040 | =item *
|
---|
1041 |
|
---|
1042 | CPANPLUS, Inline, and Module::Build will become core modules.
|
---|
1043 |
|
---|
1044 | =item *
|
---|
1045 |
|
---|
1046 | The ability to write true lexically scoped pragmas will be introduced.
|
---|
1047 |
|
---|
1048 | =item *
|
---|
1049 |
|
---|
1050 | Work will continue on the bytecompiler and byteloader.
|
---|
1051 |
|
---|
1052 | =item *
|
---|
1053 |
|
---|
1054 | v-strings as they currently exist are scheduled to be deprecated. The
|
---|
1055 | v-less form (1.2.3) will become a "version object" when used with C<use>,
|
---|
1056 | C<require>, and C<$VERSION>. $^V will also be a "version object" so the
|
---|
1057 | printf("%vd",...) construct will no longer be needed. The v-ful version
|
---|
1058 | (v1.2.3) will become obsolete. The equivalence of strings and v-strings (e.g.
|
---|
1059 | that currently 5.8.0 is equal to "\5\8\0") will go away. B<There may be no
|
---|
1060 | deprecation warning for v-strings>, though: it is quite hard to detect when
|
---|
1061 | v-strings are being used safely, and when they are not.
|
---|
1062 |
|
---|
1063 | =item *
|
---|
1064 |
|
---|
1065 | 5.005 Threads Will Be Removed
|
---|
1066 |
|
---|
1067 | =item *
|
---|
1068 |
|
---|
1069 | The C<$*> Variable Will Be Removed
|
---|
1070 | (it was deprecated a long time ago)
|
---|
1071 |
|
---|
1072 | =item *
|
---|
1073 |
|
---|
1074 | Pseudohashes Will Be Removed
|
---|
1075 |
|
---|
1076 | =back
|
---|
1077 |
|
---|
1078 | =head1 Reporting Bugs
|
---|
1079 |
|
---|
1080 | If you find what you think is a bug, you might check the articles
|
---|
1081 | recently posted to the comp.lang.perl.misc newsgroup and the perl
|
---|
1082 | bug database at http://bugs.perl.org/ . There may also be
|
---|
1083 | information at http://www.perl.com/ , the Perl Home Page.
|
---|
1084 |
|
---|
1085 | If you believe you have an unreported bug, please run the B<perlbug>
|
---|
1086 | program included with your release. Be sure to trim your bug down
|
---|
1087 | to a tiny but sufficient test case. Your bug report, along with the
|
---|
1088 | output of C<perl -V>, will be sent off to [email protected] to be
|
---|
1089 | analysed by the Perl porting team. You can browse and search
|
---|
1090 | the Perl 5 bugs at http://bugs.perl.org/
|
---|
1091 |
|
---|
1092 | =head1 SEE ALSO
|
---|
1093 |
|
---|
1094 | The F<Changes> file for exhaustive details on what changed.
|
---|
1095 |
|
---|
1096 | The F<INSTALL> file for how to build Perl.
|
---|
1097 |
|
---|
1098 | The F<README> file for general stuff.
|
---|
1099 |
|
---|
1100 | The F<Artistic> and F<Copying> files for copyright information.
|
---|
1101 |
|
---|
1102 | =cut
|
---|