40 lines
709 B
C
40 lines
709 B
C
/* strncmp -- compare two strings, stop after n bytes.
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This function is in the public domain. */
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/*
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@deftypefn Supplemental int strncmp (const char *@var{s1}, const char *@var{s2}, size_t @var{n})
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Compares the first @var{n} bytes of two strings, returning a value as
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@code{strcmp}.
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@end deftypefn
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*/
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#include <ansidecl.h>
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#ifdef ANSI_PROTOTYPES
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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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int
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strncmp(s1, s2, n)
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const char *s1, *s2;
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register size_t n;
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{
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register unsigned char u1, u2;
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while (n-- > 0)
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{
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u1 = (unsigned char) *s1++;
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u2 = (unsigned char) *s2++;
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if (u1 != u2)
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return u1 - u2;
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if (u1 == '\0')
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return 0;
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}
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return 0;
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}
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