'\" t .\" Copyright (C), 1995, Graeme W. Wilford. (Wilf.) .\" .\" SPDX-License-Identifier: Linux-man-pages-copyleft .\" .\" Wed Jun 14 16:10:28 BST 1995 Wilf. (G.Wilford@@ee.surrey.ac.uk) .\" .TH re_comp 3 2023-07-20 "Linux man-pages 6.05.01" .SH NAME re_comp, re_exec \- BSD regex functions .SH LIBRARY Standard C library .RI ( libc ", " \-lc ) .SH SYNOPSIS .nf .B #define _REGEX_RE_COMP .B #include .B #include .PP .BI "[[deprecated]] char *re_comp(const char *" regex ); .BI "[[deprecated]] int re_exec(const char *" string ); .fi .SH DESCRIPTION .BR re_comp () is used to compile the null-terminated regular expression pointed to by .IR regex . The compiled pattern occupies a static area, the pattern buffer, which is overwritten by subsequent use of .BR re_comp (). If .I regex is NULL, no operation is performed and the pattern buffer's contents are not altered. .PP .BR re_exec () is used to assess whether the null-terminated string pointed to by .I string matches the previously compiled .IR regex . .SH RETURN VALUE .BR re_comp () returns NULL on successful compilation of .I regex otherwise it returns a pointer to an appropriate error message. .PP .BR re_exec () returns 1 for a successful match, zero for failure. .SH ATTRIBUTES For an explanation of the terms used in this section, see .BR attributes (7). .TS allbox; lbx lb lb l l l. Interface Attribute Value T{ .na .nh .BR re_comp (), .BR re_exec () T} Thread safety MT-Unsafe .TE .sp 1 .SH STANDARDS None. .SH HISTORY 4.3BSD. .PP These functions are obsolete; the functions documented in .BR regcomp (3) should be used instead. .SH SEE ALSO .BR regcomp (3), .BR regex (7), GNU regex manual