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CS 456 - Systems Programming

Spring 2024

Displaying ./code/jan31/fd2.c

#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>

#define arr 100

int main (int argc, char **argv){

	if (argc < 2){
	   fprintf(stderr, "Usage %s file\n",argv[0]);
	   exit(1);
	}
	//open a file, print it's file descriptor, then exit)

	int fi[arr]; // array for file descriptors


	for (int i = 1; i < argc; i++){
	    
		int fd = open(argv[i], O_RDONLY);

		fi[i] = fd;

		
	}

	for (int i = 1; i < argc; i++){
	    
		printf("fd of %s: %d\n", argv[i], fi[i]);
		
	}

	for (int i = 1; i < argc; i++){
	    
		close(fi[i]);
		
	}



		
	
	

	return 0;

}