strstr
locate a substring in a string
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INTERFACE
#include <string.h> char strstr ( const char *big, const char *little ) char strcasestr ( const char *big, const char *little ) char strnstr ( const char *big, const char *little, size_t len ) #include <xlocale.h> char strcasestr_l ( const char *big, const char *little, locale_t loc )
DESCRIPTION
The strstr function locates the first occurrence of the null-terminated string \c little in the null-terminated string \c big.
The strcasestr function is similar to strstr , but ignores the case of both strings.
The strnstr function locates the first occurrence of the null-terminated string \c little in the string \c big, where not more than \c len characters are searched. Characters that appear after a \\0 character are not searched. Since the strnstr function is a FreeBSD specific API, it should only be used when portability is not a concern.
While the strcasestr function uses the current locale, the strcasestr_l function may be passed a locale directly. See xlocale for more information.
RETURN VALUES
If little is an empty string, big is returned; if little occurs nowhere in big, NULL is returned; otherwise a pointer to the first character of the first occurrence of little is returned.
SEE ALSO
memchr, strchr, strcspn, strpbrk, strrchr, strspn, strtok
STANDARDS
The strstr function conforms to ISO/IEC 9899:1990 ("ISO C90").