Section: POSIX Programmer's Manual (1P)
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.
--- identify SCCS files (DEVELOPMENT
what [-s] file...
utility shall search the given files for all occurrences of the pattern
substitutes for the %Z
% keyword ("@(#)"
and shall write to standard output what follows until the first
occurrence of one of the following:
" > newline \ NUL
utility shall conform to the Base Definitions volume of POSIX.1-2008,
, Utility Syntax Guidelines.
The following option shall be supported:
Quit after finding the first occurrence of the pattern in each file.
The following operands shall be supported:
A pathname of a file to search.
The input files shall be of any file type.
The following environment variables shall affect the execution of
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.)
If set to a non-empty string value, override the values of all the
other internationalization variables.
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).
Determine the locale that should be used to affect the format and
contents of diagnostic messages written to standard error.
Determine the location of message catalogs for the processing of
The standard output shall consist of the following for each
"%s:\n\t%s\n", <pathname>, <identification string>
The standard error shall be used only for diagnostic messages.
The following exit values shall be returned:
Any matches were found.
CONSEQUENCES OF ERRORS
The following sections are informative.
utility is intended to be used in conjunction with the SCCS command
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
file using that library routine.
If the C-language program in file
char ident = "@(#)identification information";
is compiled to yield
then the command:
what f.c f.o a.out
The Base Definitions volume of POSIX.1-2008,
Chapter 8, Environment Variables,
Section 12.2, Utility Syntax Guidelines
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
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