'\" t .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) .\" .\" SPDX-License-Identifier: Linux-man-pages-copyleft .\" .\" References consulted: .\" Linux libc source code .\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) .\" 386BSD man pages .\" Modified Mon Apr 12 12:51:24 1993, David Metcalfe .\" 2006-05-19, Justin Pryzby .\" Document strchrnul(3). .\" .TH strchr 3 2023-10-31 "Linux man-pages 6.06" .SH NAME strchr, strrchr, strchrnul \- locate character in string .SH LIBRARY Standard C library .RI ( libc ", " \-lc ) .SH SYNOPSIS .nf .B #include .P .BI "char *strchr(const char *" s ", int " c ); .BI "char *strrchr(const char *" s ", int " c ); .P .BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */" .B #include .P .BI "char *strchrnul(const char *" s ", int " c ); .fi .SH DESCRIPTION The .BR strchr () function returns a pointer to the first occurrence of the character .I c in the string .IR s . .P The .BR strrchr () function returns a pointer to the last occurrence of the character .I c in the string .IR s . .P The .BR strchrnul () function is like .BR strchr () except that if .I c is not found in .IR s , then it returns a pointer to the null byte at the end of .IR s , rather than NULL. .P Here "character" means "byte"; these functions do not work with wide or multibyte characters. .SH RETURN VALUE The .BR strchr () and .BR strrchr () functions return a pointer to the matched character or NULL if the character is not found. The terminating null byte is considered part of the string, so that if .I c is specified as \[aq]\e0\[aq], these functions return a pointer to the terminator. .P The .BR strchrnul () function returns a pointer to the matched character, or a pointer to the null byte at the end of .I s (i.e., .IR "s+strlen(s)" ) if the character is not found. .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 strchr (), .BR strrchr (), .BR strchrnul () T} Thread safety MT-Safe .TE .SH STANDARDS .TP .BR strchr () .TQ .BR strrchr () C11, POSIX.1-2008. .TP .BR strchrnul () GNU. .SH HISTORY .TP .BR strchr () .TQ .BR strrchr () POSIX.1-2001, C89, SVr4, 4.3BSD. .TP .BR strchrnul () glibc 2.1.1. .SH SEE ALSO .BR memchr (3), .BR string (3), .BR strlen (3), .BR strpbrk (3), .BR strsep (3), .BR strspn (3), .BR strstr (3), .BR strtok (3), .BR wcschr (3), .BR wcsrchr (3)