| 1 | FILE(1P) POSIX Programmer's Manual FILE(1P)
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| 2 |
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| 3 |
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| 4 |
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| 5 | PROLOG
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| 6 | This manual page is part of the POSIX Programmer's Man-
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| 7 | ual. The Linux implementation of this interface may
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| 8 | differ (consult the corresponding Linux manual page for
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| 9 | details of Linux behavior), or the interface may not be
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| 10 | implemented on Linux.
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| 11 |
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| 12 | NAME
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| 13 | file - determine file type
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| 14 |
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| 15 | SYNOPSIS
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| 16 | file [-dh][-M file][-m file] file ...
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| 17 |
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| 18 | file -i [-h] file ...
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| 19 |
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| 20 |
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| 21 | DESCRIPTION
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| 22 | The file utility shall perform a series of tests in
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| 23 | sequence on each specified file in an attempt to clas-
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| 24 | sify it:
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| 25 |
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| 26 | 1. If file does not exist, cannot be read, or its file
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| 27 | status could not be determined, the output shall
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| 28 | indicate that the file was processed, but that its
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| 29 | type could not be determined.
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| 30 |
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| 31 |
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| 32 | 2. If the file is not a regular file, its file type
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| 33 | shall be identified. The file types directory,
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| 34 | FIFO, socket, block special, and character special
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| 35 | shall be identified as such. Other implementation-
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| 36 | defined file types may also be identified. If file
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| 37 | is a symbolic link, by default the link shall be
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| 38 | resolved and file shall test the type of file refer-
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| 39 | enced by the symbolic link. (See the -h and -i
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| 40 | options below.)
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| 41 |
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| 42 |
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| 43 | 3. If the length of file is zero, it shall be identi-
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| 44 | fied as an empty file.
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| 45 |
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| 46 |
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| 47 | 4. The file utility shall examine an initial segment of
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| 48 | file and shall make a guess at identifying its con-
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| 49 | tents based on position-sensitive tests. (The answer
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| 50 | is not guaranteed to be correct; see the -d, -M, and
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| 51 | -m options below.)
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| 52 |
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| 53 |
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| 54 | 5. The file utility shall examine file and make a guess
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| 55 | at identifying its contents based on context-sensi-
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| 56 | tive default system tests. (The answer is not guar-
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| 57 | anteed to be correct.)
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| 58 |
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| 59 |
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| 60 | 6. The file shall be identified as a data file.
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| 61 |
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| 62 |
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| 63 | If file does not exist, cannot be read, or its file sta-
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| 64 | tus could not be determined, the output shall indicate
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| 65 | that the file was processed, but that its type could not
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| 66 | be determined.
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| 67 |
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| 68 | If file is a symbolic link, by default the link shall be
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| 69 | resolved and file shall test the type of file referenced
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| 70 | by the symbolic link.
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| 71 |
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| 72 | OPTIONS
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| 73 | The file utility shall conform to the Base Definitions
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| 74 | volume of IEEE Std 1003.1-2001, Section 12.2, Utility
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| 75 | Syntax Guidelines, except that the order of the -m, -d,
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| 76 | and -M options shall be significant.
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| 77 |
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| 78 | The following options shall be supported by the imple-
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| 79 | mentation:
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| 80 |
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| 81 | -d Apply any position-sensitive default system tests
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| 82 | and context-sensitive default system tests to the
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| 83 | file. This is the default if no -M or -m option
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| 84 | is specified.
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| 85 |
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| 86 | -h When a symbolic link is encountered, identify the
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| 87 | file as a symbolic link. If -h is not specified
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| 88 | and file is a symbolic link that refers to a
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| 89 | nonexistent file, file shall identify the file as
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| 90 | a symbolic link, as if -h had been specified.
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| 91 |
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| 92 | -i If a file is a regular file, do not attempt to
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| 93 | classify the type of the file further, but iden-
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| 94 | tify the file as specified in the STDOUT section.
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| 95 |
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| 96 | -M file
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| 97 | Specify the name of a file containing position-
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| 98 | sensitive tests that shall be applied to a file
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| 99 | in order to classify it (see the EXTENDED
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| 100 | DESCRIPTION). No position-sensitive default sys-
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| 101 | tem tests nor context-sensitive default system
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| 102 | tests shall be applied unless the -d option is
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| 103 | also specified.
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| 104 |
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| 105 | -m file
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| 106 | Specify the name of a file containing position-
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| 107 | sensitive tests that shall be applied to a file
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| 108 | in order to classify it (see the EXTENDED
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| 109 | DESCRIPTION).
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| 110 |
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| 111 |
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| 112 | If the -m option is specified without specifying the -d
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| 113 | option or the -M option, position-sensitive default sys-
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| 114 | tem tests shall be applied after the position-sensitive
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| 115 | tests specified by the -m option. If the -M option is
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| 116 | specified with the -d option, the -m option, or both, or
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| 117 | the -m option is specified with the -d option, the con-
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| 118 | catenation of the position-sensitive tests specified by
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| 119 | these options shall be applied in the order specified by
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| 120 | the appearance of these options. If a -M or -m file
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| 121 | option-argument is -, the results are unspecified.
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| 122 |
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| 123 | OPERANDS
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| 124 | The following operand shall be supported:
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| 125 |
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| 126 | file A pathname of a file to be tested.
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| 127 |
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| 128 |
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| 129 | STDIN
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| 130 | Not used.
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| 131 |
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| 132 | INPUT FILES
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| 133 | The file can be any file type.
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| 134 |
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| 135 | ENVIRONMENT VARIABLES
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| 136 | The following environment variables shall affect the
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| 137 | execution of file:
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| 138 |
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| 139 | LANG Provide a default value for the internationaliza-
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| 140 | tion variables that are unset or null. (See the
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| 141 | Base Definitions volume of IEEE Std 1003.1-2001,
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| 142 | Section 8.2, Internationalization Variables for
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| 143 | the precedence of internationalization variables
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| 144 | used to determine the values of locale cate-
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| 145 | gories.)
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| 146 |
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| 147 | LC_ALL If set to a non-empty string value, override the
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| 148 | values of all the other internationalization
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| 149 | variables.
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| 150 |
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| 151 | LC_CTYPE
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| 152 | Determine the locale for the interpretation of
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| 153 | sequences of bytes of text data as characters
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| 154 | (for example, single-byte as opposed to multi-
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| 155 | byte characters in arguments and input files).
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| 156 |
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| 157 | LC_MESSAGES
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| 158 | Determine the locale that should be used to
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| 159 | affect the format and contents of diagnostic mes-
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| 160 | sages written to standard error and informative
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| 161 | messages written to standard output.
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| 162 |
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| 163 | NLSPATH
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| 164 | Determine the location of message catalogs for
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| 165 | the processing of LC_MESSAGES .
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| 166 |
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| 167 |
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| 168 | ASYNCHRONOUS EVENTS
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| 169 | Default.
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| 170 |
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| 171 | STDOUT
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| 172 | In the POSIX locale, the following format shall be used
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| 173 | to identify each operand, file specified:
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| 174 |
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| 175 |
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| 176 | "%s: %s\n", <file>, <type>
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| 177 |
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| 178 | The values for <type> are unspecified, except that in
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| 179 | the POSIX locale, if file is identified as one of the
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| 180 | types listed in the following table, <type> shall con-
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| 181 | tain (but is not limited to) the corresponding string,
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| 182 | unless the file is identified by a position-sensitive
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| 183 | test specified by a -M or -m option. Each space shown in
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| 184 | the strings shall be exactly one <space>.
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| 185 |
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| 186 | Table: File Utility Output Strings
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| 187 |
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| 188 | If file is: <type> shall contain the Notes
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| 189 | string:
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| 190 | Nonexistent cannot open
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| 191 | Block special block special 1
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| 192 | Character special character special 1
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| 193 | Directory directory 1
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| 194 | FIFO fifo 1
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| 195 | Socket socket 1
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| 196 | Symbolic link symbolic link to 1
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| 197 | Regular file regular file 1,2
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| 198 | Empty regular file empty 3
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| 199 | Regular file that cannot be read cannot open 3
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| 200 | Executable binary executable 4,6
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| 201 | ar archive library (see ar) archive 4,6
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| 202 | Extended cpio format (see pax) cpio archive 4,6
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| 203 | Extended tar format (see ustar in pax) tar archive 4,6
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| 204 | Shell script commands text 5,6
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| 205 | C-language source c program text 5,6
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| 206 | FORTRAN source fortran program text 5,6
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| 207 | Regular file whose type cannot be deter- data
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| 208 | mined
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| 209 |
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| 210 | Notes:
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| 211 |
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| 212 | 1. This is a file type test.
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| 213 |
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| 214 |
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| 215 | 2. This test is applied only if the -i option is
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| 216 | specified.
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| 217 |
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| 218 |
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| 219 | 3. This test is applied only if the -i option is
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| 220 | not specified.
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| 221 |
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| 222 |
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| 223 | 4. This is a position-sensitive default system
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| 224 | test.
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| 225 |
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| 226 |
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| 227 | 5. This is a context-sensitive default system
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| 228 | test.
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| 229 |
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| 230 |
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| 231 | 6. Position-sensitive default system tests and
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| 232 | context-sensitive default system tests are
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| 233 | not applied if the -M option is specified
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| 234 | unless the -d option is also specified.
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| 235 |
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| 236 |
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| 237 |
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| 238 | In the POSIX locale, if file is identified as a symbolic
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| 239 | link (see the -h option), the following alternative out-
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| 240 | put format shall be used:
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| 241 |
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| 242 |
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| 243 | "%s: %s %s\n", <file>, <type>, <contents of link>"
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| 244 |
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| 245 | If the file named by the file operand does not exist,
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| 246 | cannot be read, or the type of the file named by the
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| 247 | file operand cannot be determined, this shall not be
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| 248 | considered an error that affects the exit status.
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| 249 |
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| 250 | STDERR
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| 251 | The standard error shall be used only for diagnostic
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| 252 | messages.
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| 253 |
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| 254 | OUTPUT FILES
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| 255 | None.
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| 256 |
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| 257 | EXTENDED DESCRIPTION
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| 258 | A file specified as an option-argument to the -m or -M
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| 259 | options shall contain one position-sensitive test per
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| 260 | line, which shall be applied to the file. If the test
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| 261 | succeeds, the message field of the line shall be printed
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| 262 | and no further tests shall be applied, with the excep-
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| 263 | tion that tests on immediately following lines beginning
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| 264 | with a single '>' character shall be applied.
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| 265 |
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| 266 | Each line shall be composed of the following four
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| 267 | <blank>-separated fields:
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| 268 |
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| 269 | offset An unsigned number (optionally preceded by a sin-
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| 270 | gle '>' character) specifying the offset, in
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| 271 | bytes, of the value in the file that is to be
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| 272 | compared against the value field of the line. If
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| 273 | the file is shorter than the specified offset,
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| 274 | the test shall fail.
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| 275 |
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| 276 | If the offset begins with the character '>', the test
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| 277 | contained in the line shall not be applied to the file
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| 278 | unless the test on the last line for which the offset
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| 279 | did not begin with a '>' was successful. By default, the
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| 280 | offset shall be interpreted as an unsigned decimal num-
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| 281 | ber. With a leading 0x or 0X, the offset shall be inter-
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| 282 | preted as a hexadecimal number; otherwise, with a lead-
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| 283 | ing 0, the offset shall be interpreted as an octal num-
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| 284 | ber.
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| 285 |
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| 286 | type The type of the value in the file to be tested.
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| 287 | The type shall consist of the type specification
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| 288 | characters c, d, f, s, and u, specifying charac-
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| 289 | ter, signed decimal, floating point, string, and
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| 290 | unsigned decimal, respectively.
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| 291 |
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| 292 | The type string shall be interpreted as the bytes from
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| 293 | the file starting at the specified offset and including
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| 294 | the same number of bytes specified by the value field.
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| 295 | If insufficient bytes remain in the file past the offset
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| 296 | to match the value field, the test shall fail.
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| 297 |
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| 298 | The type specification characters d, f, and u can be
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| 299 | followed by an optional unsigned decimal integer that
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| 300 | specifies the number of bytes represented by the type.
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| 301 | The type specification character f can be followed by an
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| 302 | optional F, D, or L, indicating that the value is of
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| 303 | type float, double, or long double, respectively. The
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| 304 | type specification characters d and u can be followed by
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| 305 | an optional C, S, I, or L, indicating that the value is
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| 306 | of type char, short, int, or long, respectively.
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| 307 |
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| 308 | The default number of bytes represented by the type
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| 309 | specifiers d, f, and u shall correspond to their respec-
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| 310 | tive C-language types as follows. If the system claims
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| 311 | conformance to the C-Language Development Utilities
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| 312 | option, those specifiers shall correspond to the default
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| 313 | sizes used in the c99 utility. Otherwise, the default
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| 314 | sizes shall be implementation-defined.
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| 315 |
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| 316 | For the type specifier characters d and u, the default
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| 317 | number of bytes shall correspond to the size of a basic
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| 318 | integer type of the implementation. For these specifier
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| 319 | characters, the implementation shall support values of
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| 320 | the optional number of bytes to be converted correspond-
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| 321 | ing to the number of bytes in the C-language types char,
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| 322 | short, int, or long. These numbers can also be specified
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| 323 | by an application as the characters C, S, I, and L,
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| 324 | respectively. The byte order used when interpreting
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| 325 | numeric values is implementation-defined, but shall cor-
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| 326 | respond to the order in which a constant of the corre-
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| 327 | sponding type is stored in memory on the system.
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| 328 |
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| 329 | For the type specifier f, the default number of bytes
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| 330 | shall correspond to the number of bytes in the basic
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| 331 | double precision floating-point data type of the under-
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| 332 | lying implementation. The implementation shall support
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| 333 | values of the optional number of bytes to be converted
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| 334 | corresponding to the number of bytes in the C-language
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| 335 | types float, double, and long double. These numbers can
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| 336 | also be specified by an application as the characters F,
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| 337 | D, and L, respectively.
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| 338 |
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| 339 | All type specifiers, except for s, can be followed by a
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| 340 | mask specifier of the form &number. The mask value shall
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| 341 | be AND'ed with the value of the input file before the
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| 342 | comparison with the value field of the line is made. By
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| 343 | default, the mask shall be interpreted as an unsigned
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| 344 | decimal number. With a leading 0x or 0X, the mask shall
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| 345 | be interpreted as an unsigned hexadecimal number; other-
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| 346 | wise, with a leading 0, the mask shall be interpreted as
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| 347 | an unsigned octal number.
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| 348 |
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| 349 | The strings byte, short, long, and string shall also be
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| 350 | supported as type fields, being interpreted as dC, dS,
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| 351 | dL, and s, respectively.
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| 352 |
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| 353 | value The value to be compared with the value from the
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| 354 | file.
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| 355 |
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| 356 | If the specifier from the type field is s or string,
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| 357 | then interpret the value as a string. Otherwise, inter-
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| 358 | pret it as a number. If the value is a string, then the
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| 359 | test shall succeed only when a string value exactly
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| 360 | matches the bytes from the file.
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| 361 |
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| 362 | If the value is a string, it can contain the following
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| 363 | sequences:
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| 364 |
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| 365 | \character
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| 366 | The backslash-escape sequences as specified in
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| 367 | the Base Definitions volume of
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| 368 | IEEE Std 1003.1-2001, Table 5-1, Escape Sequences
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| 369 | and Associated Actions ( '\\', '\a', '\b', '\f',
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| 370 | '\n', '\r', '\t', '\v' ). The results of using
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| 371 | any other character, other than an octal digit,
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| 372 | following the backslash are unspecified.
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| 373 |
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| 374 | \octal
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| 375 | Octal sequences that can be used to represent
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| 376 | characters with specific coded values. An octal
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| 377 | sequence shall consist of a backslash followed by
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| 378 | the longest sequence of one, two, or three octal-
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| 379 | digit characters (01234567). If the size of a
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| 380 | byte on the system is greater than 9 bits, the
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| 381 | valid escape sequence used to represent a byte is
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| 382 | implementation-defined.
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| 383 |
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| 384 |
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| 385 | By default, any value that is not a string shall be
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| 386 | interpreted as a signed decimal number. Any such value,
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| 387 | with a leading 0x or 0X, shall be interpreted as an
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| 388 | unsigned hexadecimal number; otherwise, with a leading
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| 389 | zero, the value shall be interpreted as an unsigned
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| 390 | octal number.
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| 391 |
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| 392 | If the value is not a string, it can be preceded by a
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| 393 | character indicating the comparison to be performed.
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| 394 | Permissible characters and the comparisons they specify
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| 395 | are as follows:
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| 396 |
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| 397 | =
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| 398 | The test shall succeed if the value from the file
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| 399 | equals the value field.
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| 400 |
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| 401 | <
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| 402 | The test shall succeed if the value from the file
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| 403 | is less than the value field.
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| 404 |
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| 405 | >
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| 406 | The test shall succeed if the value from the file
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| 407 | is greater than the value field.
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| 408 |
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| 409 | &
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| 410 | The test shall succeed if all of the set bits in
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| 411 | the value field are set in the value from the
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| 412 | file.
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| 413 |
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| 414 | ^
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| 415 | The test shall succeed if at least one of the set
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| 416 | bits in the value field is not set in the value
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| 417 | from the file.
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| 418 |
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| 419 | x
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| 420 | The test shall succeed if the file is large
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| 421 | enough to contain a value of the type specified
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| 422 | starting at the offset specified.
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| 423 |
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| 424 |
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| 425 | message
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| 426 | The message to be printed if the test succeeds.
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| 427 | The message shall be interpreted using the nota-
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| 428 | tion for the printf formatting specification; see
|
|---|
| 429 | printf(). If the value field was a string, then
|
|---|
| 430 | the value from the file shall be the argument for
|
|---|
| 431 | the printf formatting specification; otherwise,
|
|---|
| 432 | the value from the file shall be the argument.
|
|---|
| 433 |
|
|---|
| 434 |
|
|---|
| 435 | EXIT STATUS
|
|---|
| 436 | The following exit values shall be returned:
|
|---|
| 437 |
|
|---|
| 438 | 0 Successful completion.
|
|---|
| 439 |
|
|---|
| 440 | >0 An error occurred.
|
|---|
| 441 |
|
|---|
| 442 |
|
|---|
| 443 | CONSEQUENCES OF ERRORS
|
|---|
| 444 | Default.
|
|---|
| 445 |
|
|---|
| 446 | The following sections are informative.
|
|---|
| 447 |
|
|---|
| 448 | APPLICATION USAGE
|
|---|
| 449 | The file utility can only be required to guess at many
|
|---|
| 450 | of the file types because only exhaustive testing can
|
|---|
| 451 | determine some types with certainty. For example, binary
|
|---|
| 452 | data on some implementations might match the initial
|
|---|
| 453 | segment of an executable or a tar archive.
|
|---|
| 454 |
|
|---|
| 455 | Note that the table indicates that the output contains
|
|---|
| 456 | the stated string. Systems may add text before or after
|
|---|
| 457 | the string. For executables, as an example, the machine
|
|---|
| 458 | architecture and various facts about how the file was
|
|---|
| 459 | link-edited may be included. Note also that on systems
|
|---|
| 460 | that recognize shell script files starting with "#!" as
|
|---|
| 461 | executable files, these may be identified as executable
|
|---|
| 462 | binary files rather than as shell scripts.
|
|---|
| 463 |
|
|---|
| 464 | EXAMPLES
|
|---|
| 465 | Determine whether an argument is a binary executable
|
|---|
| 466 | file:
|
|---|
| 467 |
|
|---|
| 468 |
|
|---|
| 469 | file "$1" | grep -Fq executable &&
|
|---|
| 470 | printf "%s is executable.\n" "$1"
|
|---|
| 471 |
|
|---|
| 472 | RATIONALE
|
|---|
| 473 | The -f option was omitted because the same effect can
|
|---|
| 474 | (and should) be obtained using the xargs utility.
|
|---|
| 475 |
|
|---|
| 476 | Historical versions of the file utility attempt to iden-
|
|---|
| 477 | tify the following types of files: symbolic link, direc-
|
|---|
| 478 | tory, character special, block special, socket, tar ar-
|
|---|
| 479 | chive, cpio archive, SCCS archive, archive library,
|
|---|
| 480 | empty, compress output, pack output, binary data, C
|
|---|
| 481 | source, FORTRAN source, assembler source, nroff/ troff/
|
|---|
| 482 | eqn/ tbl source troff output, shell script, C shell
|
|---|
| 483 | script, English text, ASCII text, various executables,
|
|---|
| 484 | APL workspace, compiled terminfo entries, and CURSES
|
|---|
| 485 | screen images. Only those types that are reasonably well
|
|---|
| 486 | specified in POSIX or are directly related to POSIX
|
|---|
| 487 | utilities are listed in the table.
|
|---|
| 488 |
|
|---|
| 489 | Historical systems have used a "magic file" named
|
|---|
| 490 | /etc/magic to help identify file types. Because it is
|
|---|
| 491 | generally useful for users and scripts to be able to
|
|---|
| 492 | identify special file types, the -m flag and a portable
|
|---|
| 493 | format for user-created magic files has been specified.
|
|---|
| 494 | No requirement is made that an implementation of file
|
|---|
| 495 | use this method of identifying files, only that users be
|
|---|
| 496 | permitted to add their own classifying tests.
|
|---|
| 497 |
|
|---|
| 498 | In addition, three options have been added to historical
|
|---|
| 499 | practice. The -d flag has been added to permit users to
|
|---|
| 500 | cause their tests to follow any default system tests.
|
|---|
| 501 | The -i flag has been added to permit users to test
|
|---|
| 502 | portably for regular files in shell scripts. The -M flag
|
|---|
| 503 | has been added to permit users to ignore any default
|
|---|
| 504 | system tests.
|
|---|
| 505 |
|
|---|
| 506 | The IEEE Std 1003.1-2001 description of default system
|
|---|
| 507 | tests and the interaction between the -d, -M, and -m
|
|---|
| 508 | options did not clearly indicate that there were two
|
|---|
| 509 | types of "default system tests". The "position-sensitive
|
|---|
| 510 | tests'' determine file types by looking for certain
|
|---|
| 511 | string or binary values at specific offsets in the file
|
|---|
| 512 | being examined. These position-sensitive tests were
|
|---|
| 513 | implemented in historical systems using the magic file
|
|---|
| 514 | described above. Some of these tests are now built into
|
|---|
| 515 | the file utility itself on some implementations so the
|
|---|
| 516 | output can provide more detail than can be provided by
|
|---|
| 517 | magic files. For example, a magic file can easily iden-
|
|---|
| 518 | tify a core file on most implementations, but cannot
|
|---|
| 519 | name the program file that dropped the core. A magic
|
|---|
| 520 | file could produce output such as:
|
|---|
| 521 |
|
|---|
| 522 |
|
|---|
| 523 | /home/dwc/core: ELF 32-bit MSB core file SPARC Version 1
|
|---|
| 524 |
|
|---|
| 525 | but by building the test into the file utility, you
|
|---|
| 526 | could get output such as:
|
|---|
| 527 |
|
|---|
| 528 |
|
|---|
| 529 | /home/dwc/core: ELF 32-bit MSB core file SPARC Version 1, from 'testprog'
|
|---|
| 530 |
|
|---|
| 531 | These extended built-in tests are still to be treated as
|
|---|
| 532 | position-sensitive default system tests even if they are
|
|---|
| 533 | not listed in /etc/magic or any other magic file.
|
|---|
| 534 |
|
|---|
| 535 | The context-sensitive default system tests were always
|
|---|
| 536 | built into the file utility. These tests looked for lan-
|
|---|
| 537 | guage constructs in text files trying to identify shell
|
|---|
| 538 | scripts, C, FORTRAN, and other computer language source
|
|---|
| 539 | files, and even plain text files. With the addition of
|
|---|
| 540 | the -m and -M options the distinction between position-
|
|---|
| 541 | sensitive and context-sensitive default system tests
|
|---|
| 542 | became important because the order of testing is impor-
|
|---|
| 543 | tant. The context-sensitive system default tests should
|
|---|
| 544 | never be applied before any position-sensitive tests
|
|---|
| 545 | even if the -d option is specified before a -m option or
|
|---|
| 546 | -M option due to the high probability that the context-
|
|---|
| 547 | sensitive system default tests will incorrectly identify
|
|---|
| 548 | arbitrary text files as text files before position-sen-
|
|---|
| 549 | sitive tests specified by the -m or -M option would be
|
|---|
| 550 | applied to give a more accurate identification.
|
|---|
| 551 |
|
|---|
| 552 | Leaving the meaning of -M - and -m - unspecified allows
|
|---|
| 553 | an existing prototype of these options to continue to
|
|---|
| 554 | work in a backwards-compatible manner. (In that imple-
|
|---|
| 555 | mentation, -M - was roughly equivalent to -d in
|
|---|
| 556 | IEEE Std 1003.1-2001.)
|
|---|
| 557 |
|
|---|
| 558 | The historical -c option was omitted as not particularly
|
|---|
| 559 | useful to users or portable shell scripts. In addition,
|
|---|
| 560 | a reasonable implementation of the file utility would
|
|---|
| 561 | report any errors found each time the magic file is
|
|---|
| 562 | read.
|
|---|
| 563 |
|
|---|
| 564 | The historical format of the magic file was the same as
|
|---|
| 565 | that specified by the Rationale in the ISO POSIX-2:1993
|
|---|
| 566 | standard for the offset, value, and message fields; how-
|
|---|
| 567 | ever, it used less precise type fields than the format
|
|---|
| 568 | specified by the current normative text. The new type
|
|---|
| 569 | field values are a superset of the historical ones.
|
|---|
| 570 |
|
|---|
| 571 | The following is an example magic file:
|
|---|
| 572 |
|
|---|
| 573 |
|
|---|
| 574 | 0 short 070707 cpio archive
|
|---|
| 575 | 0 short 0143561 Byte-swapped cpio archive
|
|---|
| 576 | 0 string 070707 ASCII cpio archive
|
|---|
| 577 | 0 long 0177555 Very old archive
|
|---|
| 578 | 0 short 0177545 Old archive
|
|---|
| 579 | 0 short 017437 Old packed data
|
|---|
| 580 | 0 string \037\036 Packed data
|
|---|
| 581 | 0 string \377\037 Compacted data
|
|---|
| 582 | 0 string \037\235 Compressed data
|
|---|
| 583 | >2 byte&0x80 >0 Block compressed
|
|---|
| 584 | >2 byte&0x1f x %d bits
|
|---|
| 585 | 0 string \032\001 Compiled Terminfo Entry
|
|---|
| 586 | 0 short 0433 Curses screen image
|
|---|
| 587 | 0 short 0434 Curses screen image
|
|---|
| 588 | 0 string <ar> System V Release 1 archive
|
|---|
| 589 | 0 string !<arch>\n__.SYMDEF Archive random library
|
|---|
| 590 | 0 string !<arch> Archive
|
|---|
| 591 | 0 string ARF_BEGARF PHIGS clear text archive
|
|---|
| 592 | 0 long 0x137A2950 Scalable OpenFont binary
|
|---|
| 593 | 0 long 0x137A2951 Encrypted scalable OpenFont binary
|
|---|
| 594 |
|
|---|
| 595 | The use of a basic integer data type is intended to
|
|---|
| 596 | allow the implementation to choose a word size commonly
|
|---|
| 597 | used by applications on that architecture.
|
|---|
| 598 |
|
|---|
| 599 | FUTURE DIRECTIONS
|
|---|
| 600 | None.
|
|---|
| 601 |
|
|---|
| 602 | SEE ALSO
|
|---|
| 603 | ar, ls, pax
|
|---|
| 604 |
|
|---|
| 605 | COPYRIGHT
|
|---|
| 606 | Portions of this text are reprinted and reproduced in
|
|---|
| 607 | electronic form from IEEE Std 1003.1, 2003 Edition,
|
|---|
| 608 | Standard for Information Technology -- Portable Operat-
|
|---|
| 609 | ing System Interface (POSIX), The Open Group Base Speci-
|
|---|
| 610 | fications Issue 6, Copyright (C) 2001-2003 by the Insti-
|
|---|
| 611 | tute of Electrical and Electronics Engineers, Inc and
|
|---|
| 612 | The Open Group. In the event of any discrepancy between
|
|---|
| 613 | this version and the original IEEE and The Open Group
|
|---|
| 614 | Standard, the original IEEE and The Open Group Standard
|
|---|
| 615 | is the referee document. The original Standard can be
|
|---|
| 616 | obtained online at http://www.open-
|
|---|
| 617 | group.org/unix/online.html .
|
|---|
| 618 |
|
|---|
| 619 |
|
|---|
| 620 |
|
|---|
| 621 | IEEE/The Open Group 2003 FILE(1P)
|
|---|
