Character string search (maximum length including specified character)

[Classification]

Standard library

[Syntax]

#include <string.h>

size_t strspn(const char *s1, const char *s2);

[Return value]

Returns the length of the portion that has been found.

[Description]

This function obtains the maximum and first length of the portion consisting of only the characters (except the null character (\0)) in the character string indicated by s2, in the character string indicated by s1.