linux-C产生临时文件

#include <stdio.h>
int main(void){
   char tmpname[L_tmpnam];
   char *filename;
   FILE *fp;
   strcpy(tmpname,"/tmp/dfXXXXXX");//file name:df...
   filename=mktemp(tmpname);//generate tempfile
   printf("temporary file name:%s\n",filename);
   
   fp=tmpfile();
   if (fp) printf("temporary file oepn.\n");
   else perror("error");
   exit(0);  
}