1file(1) User Commands file(1)
2
6 file - determine file type
7
9 /usr/bin/file [-dh] [-m mfile] [-M Mfile] [-f ffile] file...
10 /usr/bin/file [-dh] [-m mfile] [-M Mfile] -f ffile
13 /usr/bin/file -i [-h] [-f ffile] file...
16 /usr/bin/file -i [-h] -f ffile
19 /usr/bin/file -c [-d] [-m mfile] [-M Mfile]
22 /usr/xpg4/bin/file [-dh] [-m mfile] [-M Mfile] [-f ffile] file...
25 /usr/xpg4/bin/file [-dh] [-m mfile] [-M Mfile] -f ffile
28 /usr/xpg4/bin/file -i [-h] [-f ffile] file...
31 /usr/xpg4/bin/file -i [-h] -f ffile
34 /usr/xpg4/bin/file -c [-d] [-m mfile] [-M Mfile]
37
40 The file utility performs a series of tests on each file supplied by
41 file and, optionally, on each file listed in ffile in an attempt to
42 classify it. If the file is not a regular file, its file type is iden‐
43 tified. The file types directory, FIFO, block special, and character
44 special are identified as such. If the file is a regular file and the
45 file is zero-length, it is identified as an empty file.
46 If file appears to be a text file, file examines the first 512 bytes
49 and tries to determine its programming language. If file is a symbolic
50 link, by default the link is followed and file tests the file to which
51 the symbolic link refers.
52 If file is a relocatable object, executable, or shared object, file
55 prints out information about the file's execution requirements. This
56 information includes the machine class, byte-ordering, static/dynamic
57 linkage, and any software or hardware capability requirements. If file
58 is a runtime linking configuration file, file prints information about
59 the target platform, including the machine class and byte-ordering.
60 By default, file will try to use the localized magic file
63 /usr/lib/locale/locale/LC_MESSAGES/magic, if it exists, to identify
64 files that have a magic number. For example, in the Japanese locale,
65 file will try to use /usr/lib/locale/ja/LC_MESSAGES/magic. If a local‐
66 ized magic file does not exist, file will utilize /etc/magic. A magic
67 number is a numeric or string constant that indicates the file type.
68 See magic(4) for an explanation of the format of /etc/magic.
69 If file does not exist, cannot be read, or its file status could not be
72 determined, it is not considered an error that affects the exit status.
73 The output will indicate that the file was processed, but that its type
74 could not be determined.
75
77 The following options are supported:
78 -c Checks the magic file for format errors. For reasons of
80 efficiency, this validation is normally not carried out.
81 -d Applies any position-sensitive and context-sensitive
84 default system tests to the file.
85 -f ffile ffile contains a list of the files to be examined.
88 -h When a symbolic link is encountered, this option identifies
91 the file as a symbolic link. If -h is not specified and
92 file is a symbolic link that refers to a non-existent file,
93 the file utility identifies the file as a symbolic link, as
94 if -h had been specified.
95 -i If a file is a regular file, this option does not attempt
98 to classify the type of file further, but identifies the
99 file as a "regular file".
100 -m mfile
103 /usr/bin/file Uses mfile as an alternate magic
104 file, instead of /etc/magic.
105 /usr/xpg4/bin/file Specifies the name of a file contain‐
108 ing position-sensitive tests that are
109 applied to a file in order to clas‐
110 sify it (see magic(4)). If the -m
111 option is specified without specify‐
112 ing the -d option or the -M option,
113 position-sensitive default system
114 tests are applied after the position-
115 sensitive tests specified by the -m
116 option.
117 -M Mfile Specifies the name of a file containing position-sensitive
121 tests that are applied to a file in order to classify it
122 (see magic(4)). No position-sensitive default system tests
123 nor context-sensitive default system tests are applied
124 unless the -d option is also specified.
125 If the -M option is specified with the -d option, the -m option, or
129 both, or if the -m option is specified with the -d option, the concate‐
130 nation of the position-sensitive tests specified by these options is
131 applied in the order specified by the appearance of these options.
132
134 The following operands are supported:
135 file A path name of a file to be tested.
137
140 See largefile(5) for the description of the behavior of file when
141 encountering files greater than or equal to 2 Gbyte ( 2^31 bytes).
142
144 Example 1 Determining if an Argument is a Binary Executable Files
145 The following example determine if an argument is a binary executable
148 file:
149 file "$1" | grep −Fq executable &&
152 printf "%s is executable.0 "$1"
153
157 See environ(5) for descriptions of the following environment variables
158 that affect the execution of file: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
159 and NLSPATH.
160
162 The following exit values are returned:
163 0 Successful completion.
165 >0 An error occurred.
168
171 /etc/magic file's magic number file
172
175 See attributes(5) for descriptions of the following attributes:
176 ┌─────────────────────────────┬─────────────────────────────┐
181 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
182 ├─────────────────────────────┼─────────────────────────────┤
183 │Availability │SUNWcsu │
184 ├─────────────────────────────┼─────────────────────────────┤
185 │CSI │Enabled │
186 ├─────────────────────────────┼─────────────────────────────┤
187 │Interface Stability │Standard │
188 └─────────────────────────────┴─────────────────────────────┘
189
191 crle(1), elfdump(1), ls(1), magic(4), attributes(5), environ(5), large‐
192 file(5), standards(5)
193SunOS 5.11 15 May 2006 file(1)