text: #include <stdio.h>
  
  extern int foo(char*);
  
  int bar(char* str){
  	char* pos = strchr(str,'a');
  	return pos - str;
  }
  
  int main(){
  	puts("begin");
  	printf("foo result: %d\n", foo("bar"));
  	printf("bar result: %d\n", bar("bar"));
  	puts("end");
  	return 0;
  }
  