C字符串处理函数的实现

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标签:C C ++ string String 数据结构 
C字符串处理函数的实现

C字符串处理函数的实现（Linux）
#include <stddef.h>
 char * ___strtok = NULL;
 
 char * strcpy(char * dest,const char *src)
 {
         char *tmp = dest;
 
         while ((*dest++ = *src++) != '\0')
                 /* nothing */;
         return tmp;
 }
 
 char * strncpy(char * dest,const char *src,size_t count)
 {
         char *tmp = dest;
 
         while (count-- && (*dest++ = *src++) != '\0')
                /* nothing */;
 
         return tmp;
 }
 
 char * strcat(char * dest, const char * src)
 {
         char *tmp = dest;
 
         while (*dest)
                 dest++;
         while ((*dest++ = *src++) != '\0')
                 ;
         return tmp;
 }
 
 char * strncat(char *dest, const char *src, size_t count)
 {
         char *tmp = dest;
         if (count) {
                 while (*dest)