WHAT(1)

NAME
what - show what versions of object modules were used to construct a file

SYNOPSIS
what [-s] file ...

DESCRIPTION
what reads each file and searches for sequences of either the form ‘$’ immediately followed by the system name (sysname) as defined by uname(3), or the form “@(#)” as inserted by the source code control system (SCCS).

When ‘$’ followed by the system name is encountered what prints the remainder of the string up to a ‘$’ or any non-printable character.

When “@(#)” is encountered what prints the remainder of the string, up to a NUL, newline, double quote, backslash, or ‘>’ character.

If the -s option is specified, only the first occurrence of an identification string in each file is printed.

EXIT STATUS
The what utility exits with a return value of 0 if any identification strings were found, or with a return value of 1 otherwise.

STANDARDS
The what utility is compliant with the X/Open System Interfaces option of the p1003.1-2008 specification.

Processing $sysname$ sequences is an OpenBSD extension.

HISTORY
The what command first appeared in the SCCS package and was rewritten for 4.0BSD for licensing reasons.