'fpos_t *position' is useful only in a call to fsetpos().
#include <stdio.h> #include <stdlib.h> int main(int argc, char *argv[]) { FILE *fp; fpos_t file_loc; if((fp=fopen("test","r"))==NULL) { printf("Cannot open file.\n"); exit(1); } fgetpos(fp, &file_loc); fclose(fp); }