strstr, strcasestr — locate a substring
Synopsis
#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);
Description
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.
Return Value
These functions return a pointer to the beginning of the located substring, or NULL if the substring is not found.
Attributes
For an explanation of the terms used in this section, see attributes(7).
| Interface | Attribute | Value |
|---|---|---|
| strstr() | Thread safety | MT-Safe |
| strcasestr() | Thread safety | MT-Safe locale |
Conforming to
strstr(): POSIX.1-2001, POSIX.1-2008, C89, C99.
The strcasestr() function is a nonstandard extension.
See Also
index(3), memchr(3), memmem(3), rindex(3), strcasecmp(3), strchr(3), string(3), strpbrk(3), strsep(3), strspn(3), strtok(3), wcsstr(3)
Colophon
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Referenced By
ab(1), index(3), memchr(3), memmem(3), signal-safety(7), strchr(3), string(3), strnstr.3bsd(3), strpbrk(3), strsep(3), strspn(3), strtok(3), wcsstr(3).
The man page strcasestr(3) is an alias of strstr(3).