Trucs

#include <stdio.h>#include <stdlib.h>void display_usage(void);int line = 0;main(int ac, char **av){  char buffer[256];  FILE *fp;  if ( ac < 2 )    {      display_usage();      exit(1);    }  if ( ( fp = fopen(av[1], "r" ) ) == NULL )    {      fprintf(stderr, "erreur fichier, %s !\n", av[1]);      exit(1);    }    line = 1;    while(fgets(buffer, 256, fp) != NULL)      fprintf(stdout, "%4d:\t%s", line++, buffer);    fclose(fp);    return 0;}void display_usage(void){  fprintf(stderr, "\nLa syntaxe est la suivante : ");  fprintf(stderr, "\nLIST_IT filename.ext\n");}