WHAT(1P) POSIX Programmer's Manual WHAT(1P)PROLOG
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NAMEwhat — identify SCCS files (DEVELOPMENT)
SYNOPSISwhat [−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 occur‐
rence 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 vari‐
ables that are unset or null. (See the Base Definitions vol‐
ume of POSIX.1‐2008, Section 8.2, Internationalization Vari‐
ables 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 oper‐
and:
"%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 rou‐
tine.
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 Electri‐
cal 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.ker‐
nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 WHAT(1P)
