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PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface
may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface
may not be implemented on Linux.
NAME
what — identify SCCS files (DEVELOPMENT)
SYNOPSIS
what [−s] file...
DESCRIPTION
The what utility shall search the given files for all occurrences of the pattern that get (see get)
substitutes for the %Z% keyword ("@(#)") and shall write to standard output what follows until the first
occurrence of one of the following:
" > newline \ NUL
OPTIONS
The what utility shall conform to the Base Definitions volume of POSIX.1‐2008, Section 12.2, Utility
Syntax Guidelines.
The following option shall be supported:
−s Quit after finding the first occurrence of the pattern in each file.
OPERANDS
The following operands shall be supported:
file A pathname of a file to search.
STDIN
Not used.
INPUT FILES
The input files shall be of any file type.
ENVIRONMENT VARIABLES
The following environment variables shall affect the execution of what:
LANG Provide a default value for the internationalization variables that are unset or null. (See the
Base Definitions volume of POSIX.1‐2008, Section 8.2, Internationalization Variables for the
precedence of internationalization variables used to determine the values of locale
categories.)
LC_ALL If set to a non-empty string value, override the values of all the other internationalization
variables.
LC_CTYPE Determine the locale for the interpretation of sequences of bytes of text data as characters
(for example, single-byte as opposed to multi-byte characters in arguments and input files).
LC_MESSAGES
Determine the locale that should be used to affect the format and contents of diagnostic
messages written to standard error.
NLSPATH Determine the location of message catalogs for the processing of LC_MESSAGES.
ASYNCHRONOUS EVENTS
Default.
STDOUT
The standard output shall consist of the following for each file operand:
"%s:\n\t%s\n", <pathname>, <identification string>
STDERR
The standard error shall be used only for diagnostic messages.
OUTPUT FILES
None.
EXTENDED DESCRIPTION
None.
EXIT STATUS
The following exit values shall be returned:
0 Any matches were found.
1 Otherwise.
CONSEQUENCES OF ERRORS
Default.
The following sections are informative.
APPLICATION USAGE
The what utility is intended to be used in conjunction with the SCCS command get, which automatically
inserts identifying information, but it can also be used where the information is inserted by any other
means.
When the string "@(#)" is included in a library routine in a shared library, it might not be found in an
a.out file using that library routine.
EXAMPLES
If the C-language program in file f.c contains:
char ident[] = "@(#)identification information";
and f.c is compiled to yield f.o and a.out, then the command:
what f.c f.o a.out
writes:
f.c:
identification information
...
f.o:
identification information
...
a.out:
identification information
...
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
get
The Base Definitions volume of POSIX.1‐2008, Chapter 8, Environment Variables, Section 12.2, Utility
Syntax Guidelines
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers, Inc
and The Open Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the event
of any discrepancy between this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at
http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are most likely to have been introduced
during the conversion of the source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 WHAT(1POSIX)