41 lines
860 B
C
41 lines
860 B
C
#include <string.h>
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/*
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** The strchr() function returns a pointer to the first occurrence of the
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** character c in the strings.
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*/
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char *strchr(const char *s1, int c)
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{
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int i = -1;
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while (s1[++i] != '\0' && s1[i] != c) ;
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return ((s1[i] == '\0') ? NULL : (void *)&s1[i]);
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}
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/*
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** The strchrnul() function is like strchr() except that if c is not found in
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** s, then it returns a pointer to the null byte at the end of s, rather
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** than NULL.
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*/
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char *strchrnul(const char *s1, int c)
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{
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int i = -1;
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while (s1[++i] != '\0' && s1[i] != c) ;
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return ((void *)&s1[i]);
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}
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/*
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** The strrchr() function returns a pointer to the last occurrence of the
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** character c in the strings.
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*/
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char *strrchr(const char *s1, int c)
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{
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void *saved;
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saved = NULL;
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for (int i = 0; s1[i] != '\0'; i++) {
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if (s1[i] == c)
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saved = (void *)&s1[i];
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}
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return (saved);
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}
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