Manpages - strstr.3

strstr, strcasestr - locate a substring

  #include <string.h>

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

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

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

The *strstr*() function finds the first occurrence of the substring needle in the string haystack. The terminating null bytes (’\0’) are not compared.

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

These functions return a pointer to the beginning of the located substring, or NULL if the substring is not found.

If needle is the empty string, the return value is always haystack itself.

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

*strstr*(): POSIX.1-2001, POSIX.1-2008, C89, C99.

The *strcasestr*() function is a nonstandard extension.

*index*(3), *memchr*(3), *memmem*(3), *rindex*(3), *strcasecmp*(3), *strchr*(3), *string*(3), *strpbrk*(3), *strsep*(3), *strspn*(3), *strtok*(3), *wcsstr*(3)

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