65 lines
1.1 KiB
C
Executable File
65 lines
1.1 KiB
C
Executable File
#define _POSIX_C_SOURCE 200809L
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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int main(int argc, char *argv[]) {
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FILE * current_input_file;
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int i = 1, j = 0; char c;
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int chars_copy = 10;
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int print_head = 0;
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int error_occurred;
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while((c = getopt(argc, argv, "n:")) != -1) {
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if(c == 'n') {
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chars_copy = atoi(optarg);
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}
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}
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i = optind;
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if(argc - i > 1) {
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print_head = 1;
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}
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for(i; i < argc; i++) {
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if(argv[i][0] == '-' && argv[i][1] == '\0') {
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current_input_file = stdin;
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}
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else {
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current_input_file = fopen(argv[i], "r");
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if(current_input_file == NULL) {
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fprintf(stderr, "%s: %s: No such file or directory\n",
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argv[0], argv[i]);
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error_occurred = 1;
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}
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}
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if(print_head) {
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printf("\n==> %s <==\n", argv[i]);
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}
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j = 0;
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c = ' ';
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while(c != EOF && j < chars_copy) {
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c = fgetc(current_input_file);
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if(c == '\n') {
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j++;
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}
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if(c != EOF) {
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fprintf(stdout, "%c", c);
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}
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}
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if(current_input_file != stdin) {
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fclose(current_input_file);
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}
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}
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if(error_occurred) {
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return 1;
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}
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else {
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return 0;
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}
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} |