re_comp(3C) Standard C Library Functions re_comp(3C)NAME
re_comp, re_exec - compile and execute regular expressions
SYNOPSIS
#include <re_comp.h>
char *re_comp(const char *string);
int re_exec(const char *string);
DESCRIPTION
The re_comp() function converts a regular expression string (RE) into
an internal form suitable for pattern matching. The re_exec() function
compares the string pointed to by the string argument with the last
regular expression passed to re_comp().
If re_comp() is called with a null pointer argument, the current regu‐
lar expression remains unchanged.
Strings passed to both re_comp() and re_exec() must be terminated by a
null byte, and may include NEWLINE characters.
The re_comp() and re_exec() functions support simple regular expres‐
sions, which are defined on the regexp(5) manual page. The regular
expressions of the form \{m\}, \{m,\}, or \{m,n\} are not supported.
RETURN VALUES
The re_comp() function returns a null pointer when the string pointed
to by the string argument is successfully converted. Otherwise, a
pointer to one of the following error message strings is returned:
No previous regular expression
Regular expression too long
unmatched \(
missing ]
too many \(\) pairs
unmatched \)
Upon successful completion, re_exec() returns 1 if string matches the
last compiled regular expression. Otherwise, re_exec() returns 0 if
string fails to match the last compiled regular expression, and −1 if
the compiled regular expression is invalid (indicating an internal
error).
ERRORS
No errors are defined.
USAGE
For portability to implementations conforming to X/Open standards prior
to SUS, regcomp(3C) and regexec(3C) are preferred to these functions.
See standards(5).
SEE ALSOgrep(1), regcmp(1), regcmp(3C), regcomp(3C), regexec(3C), reg‐
expr(3GEN), regexp(5), standards(5)SunOS 5.10 26 Feb 1997 re_comp(3C)