????????linux???????????????

????1??Linux??????????????????

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????3????????????????????????

????4??????????????亯???

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???????????ο????????http://blog.csdn.net/tnndye/article/details/12784237??

????10??8?????????????-????????/??????

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????2?????C??strstr

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??????????ο??????????C????

????[cpp] view plaincopyprint?

????char *mystrstr(char *s1 ?? char *s2)

????{

????if(*s1==0)

????{

????if(*s2)

????return(char*)NULL;

????return (char*)s1;

????}

????while(*s1)

????{

????int i=0;

????while(1)

????{

????if(s2[i]==0)

????return s1;

????if(s2[i]!=s1[i])

????break;

????i++;

????}

????s1++;

????}

????return (char*)NULL;

????}

????char *mystrstr(char *s1 ?? char *s2)

????{

????if(*s1==0)

????{

????if(*s2)

????return(char*)NULL;

????return (char*)s1;

????}

????while(*s1)

????{

????int i=0;

????while(1)

????{

????if(s2[i]==0)

????return s1;

????if(s2[i]!=s1[i])

????break;

????i++;

????}

????s1++;

????}

????return (char*)NULL;

????}