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STRSTR(3)                  Library Functions Manual                  STRSTR(3)

NAME
     strstr, strcasestr, strnstr - locate a substring in a string

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #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);

DESCRIPTION
     The strstr() function locates the first occurrence of the nul-terminated
     string little in the nul-terminated string big.

     The strcasestr() function is similar to strstr(), but ignores the case of
     both strings.  The strnstr() function locates the first occurrence of the
     NUL-terminated string little in the string big, where not more than len
     characters are searched.  Characters that appear after a `\0' character
     are not searched.  Since the strnstr() function is a NetBSD specific API,
     it should only be used when portability is not a concern.

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.

EXAMPLES
     The following sets the pointer ptr to the "Bar Baz" portion of
     largestring:

           const char *largestring = "Foo Bar Baz";
           const char *smallstring = "Bar";
           char *ptr;

           ptr = strstr(largestring, smallstring);

SEE ALSO
     index(3), memchr(3), rindex(3), strchr(3), strcspn(3), strpbrk(3),
     strrchr(3), strsep(3), strspn(3), strtok(3)

STANDARDS
     The strstr() function conforms to ISO/IEC 9899:1990 ("ISO C90").

HISTORY
     The strnstr() function originated in FreeBSD.

NetBSD 10.99                  September 24, 2014                  NetBSD 10.99