61 lines
1.2 KiB
C
61 lines
1.2 KiB
C
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/*
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FUNCTION
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<<memchr>>---find character in memory
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INDEX
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memchr
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ANSI_SYNOPSIS
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#include <string.h>
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void *memchr(const void *<[src]>, int <[c]>, size_t <[length]>);
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TRAD_SYNOPSIS
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#include <string.h>
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void *memchr(<[src]>, <[c]>, <[length]>)
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void *<[src]>;
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void *<[c]>;
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size_t <[length]>;
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DESCRIPTION
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This function searches memory starting at <<*<[src]>>> for the
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character <[c]>. The search only ends with the first
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occurrence of <[c]>, or after <[length]> characters; in
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particular, <<NULL>> does not terminate the search.
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RETURNS
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If the character <[c]> is found within <[length]> characters
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of <<*<[src]>>>, a pointer to the character is returned. If
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<[c]> is not found, then <<NULL>> is returned.
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PORTABILITY
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<<memchr>> requires no supporting OS subroutines.
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QUICKREF
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memchr ansi pure
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*/
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#include <ansidecl.h>
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#ifdef __STDC__
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#include <stddef.h>
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#else
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#define size_t unsigned long
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#endif
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PTR
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memchr (src_void, c, length)
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register const PTR src_void;
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int c;
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size_t length;
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{
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const unsigned char *src = (const unsigned char *)src_void;
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while (--length >= 0)
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{
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if (*src == c)
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return (PTR)src;
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src++;
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}
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return NULL;
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}
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