strcasestr(3)

strcasestr3

String case-insensitive search substring

Usage

#define _GNU_SOURCE  // See feature_test_macros(7)
#include <string.h>

char *strcasestr(const char *haystack, const char *needle);

Library

Standard C library (libc, -lc)

Overview

strcasestr() is like strstr(), but ignores the case of both arguments.

Return value

See strstr(3).

Attributes

For an explanation of the terms used in this section, see attributes(7).

InterfaceAttributeValue
strcasestr()Thread safetyMT-Safe locale

Releases

11 releases since Debian 4.0 (Etch); the text changed 10 times.

  1. 4.0
  2. 5.0
  3. 6.0
  4. 7
  5. 8
  6. 9
  7. 10
  8. 11
  9. 12
  10. 13
  11. Arch

Standards

GNU.

History

GNU.

From man-pages 6.19-1 in Arch Linux 2026-11-01. Parsed by carta from the page's man source.