cp.c

#include <stdio.h>
#include <strings.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
    FILE *src, *dst;
    if (argc < 3) {
        fprintf(stderr, "Usage: %s source destination\n", argv[0]); 
        exit(EXIT_FAILURE);
    }

    if ((src = fopen(argv[1], "r")) == NULL) {
        printf("Could not open source :%s \n", argv[1]); 
        exit(EXIT_FAILURE);
      }
    if ((dst = fopen(argv[2], "w")) == NULL) {
        printf("Could not open destination :%s \n", argv[2]); 
        exit(EXIT_FAILURE);
    }
    int ch;

    while ((ch = getc(src)) != EOF) {
        printf("%c", ch);
        fprintf(dst, "%c", ch);
    }
    if (fclose(src) != 0) {
        printf("Could not close source :%s \n", argv[1]); 
        exit(EXIT_FAILURE);
    }
    if (fclose(dst) != 0) {
        printf("Could not close destination :%s \n", argv[2]); 
        exit(EXIT_FAILURE);
    }
    printf("Copies %s to %s\n", argv[1], argv[2]);
    return 0;
}