z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

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Options
v If the variable _UNIX03=YES is set, a space is used to separate the file name
and the type.
v If the variable _UNIX03 is unset or is not set to YES, a tab is used to separate
the file name and the file type.
The file utility uses three types of tests to determine the file type: the file attribute
tests, the position-sensitive tests and the context-sensitive tests.
v The ″file attribute tests″ determine file types such as directory, character special,
FIFO, socket, symbolic link, and external link.
v The ″position-sensitive tests’’ determine file types by looking for certain string or
binary values at specific offsets in the file being examined. The ″default
position-sensitive tests″ are defined by:
– The /etc/magic file
– The AMODE test built into the file utility
If a magic file test succeeds, the message field of the line will be printed and no
further tests will be applied, except for tests on immediately following lines
beginning with a single ’>’ character.
v The ″default context-sensitive tests″ are built into the file utility. These tests look
for language constructs in text files trying to identify shell scripts, C, FORTRAN,
and other computer language source files, and even plain text files. The ″default
context-sensitive tests″ will never be applied before any ″position-sensitive tests″
even if the -d option is specified before an -m magic option or -M magic option.
–c Only checks the file magic (specified by -m or -M) and /etc/magic (If the
semantics imply it, see ″Usage Notes″) for validity of format.
-d Apply any default position-sensitive tests and default context-sensitive tests
to the file. This is the default if no -M or -m option is specified. See ″Usage
Notes″.
-E Uses the magic file and bypasses the checking of regular files for
executables.
–f filelist
Examines the files listed in the file filelist.
-h When a symbolic link is encountered, identify file as a symbolic link instead
of following the link.
If -h is not specified and
file is an external link or file is a symbolic link referring to a nonexistent
file:
If the variable _UNIX03=YES is set
The type will be reported as if -h was specified.
If the variable _UNIX03 is unset or is not set to YES
The type will be reported as if -h was not specified.
-i If file is a regular file, does not attempt to classify the type of the file further.
This option can only be used with -h and -f options. See ″Usage Notes″ for
the file types that file command does not attempt to classify.
–M magic
Uses the file magic to classify the file type. No default position-sensitive
file
Chapter 2. Shell command descriptions 277