54 lines
845 B
C
54 lines
845 B
C
/*
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FUNCTION
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<<strspn>>---find initial match
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INDEX
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strspn
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SYNOPSIS
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#include <string.h>
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size_t strspn(const char *<[s1]>, const char *<[s2]>);
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DESCRIPTION
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This function computes the length of the initial segment of
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the string pointed to by <[s1]> which consists entirely of
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characters from the string pointed to by <[s2]> (excluding the
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terminating null character).
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RETURNS
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<<strspn>> returns the length of the segment found.
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PORTABILITY
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<<strspn>> is ANSI C.
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<<strspn>> requires no supporting OS subroutines.
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QUICKREF
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strspn ansi pure
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*/
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#include <string.h>
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size_t
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_DEFUN (strspn, (s1, s2),
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_CONST char *s1 _AND
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_CONST char *s2)
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{
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_CONST char *s = s1;
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_CONST char *c;
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while (*s1)
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{
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for (c = s2; *c; c++)
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{
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if (*s1 == *c)
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break;
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}
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if (*c == '\0')
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break;
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s1++;
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}
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return s1 - s;
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}
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