谁能告诉我strstr 是干什么用的

请举例子！！3Q

char *strstr( const char *string, const char *strCharSet );

The strstr function returns a pointer to the first occurrence of strCharSet in string. The search does not include terminating null characters.

strstr函数返回一个指针，该指针指向string串中第一次出现strCharSet的地方．搜索不包括终止的null字符！

Example

/* STRSTR.C */

#include <string.h> #include <stdio.h>

char str[] = "lazy"; char string[] = "The quick brown dog jumps over the lazy fox"; char fmt1[] = " 1 2 3 4 5"; char fmt2[] = "12345678901234567890123456789012345678901234567890";

void main( void ) { char *pdest; int result; printf( "String to be searched:\n\t%s\n", string ); printf( "\t%s\n\t%s\n\n", fmt1, fmt2 ); pdest = strstr( string, str ); result = pdest - string + 1; if( pdest != NULL ) printf( "%s found at position %d\n\n", str, result ); else printf( "%s not found\n", str ); }