Added -u option

This commit is contained in:
Gitea 2020-12-01 20:32:26 -06:00
parent 9a42532595
commit 75632e656a

84
cat.c
View file

@ -1,35 +1,75 @@
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <unistd.h>
int main(int argc, char *argv[]) { int main(int argc, char *argv[]) {
FILE * in_file; FILE * current_input_file;
int i, error = 0; int i; char c;
char c;
int using_unbuffered_output;
if(argc == 1) {
in_file = stdin; int error_occurred;
for(c = fgetc(in_file); c != EOF; c = fgetc(in_file)) {
fprintf(stdout, "%c", c);
}
}
for(i = 1; i < argc; i++) { for(i = 1; i < argc; i++) {
if(argv[i][0] == '-' && argv[i][1] == '\0') if(argv[i][0] == '-') {
in_file = stdin; if(argv[i][1] == 'u') {
else { using_unbuffered_output = 1;
in_file = fopen(argv[i], "r"); i = argc;
if(in_file == NULL) {
fprintf(stderr, "Cannot find file %s\n", argv[i]);
error = 1;
continue;
} }
} }
for(c = fgetc(in_file); c != EOF; c = fgetc(in_file))
fprintf(stdout, "%c", c);
} }
if(error) if(argc == 1) {
current_input_file = stdin;
for(c = fgetc(current_input_file); c != EOF;
c = fgetc(current_input_file)) {
if(using_unbuffered_output) {
write(1, &c, 1);
}
else {
fprintf(stdout, "%c", c);
}
}
fclose(current_input_file);
}
for(i = 1; i < argc; i++) {
if(argv[i][0] == '-' && argv[i][1] == '\0') {
current_input_file = stdin;
}
else if(argv[i][0] == '-' && argv[i][1] == 'u' &&
argv[i][2] == '\0') {
if(argc > 2) {
continue;
}
else {
current_input_file = stdin;
}
}
else {
current_input_file = fopen(argv[i], "r");
if(current_input_file == NULL) {
fprintf(stderr, "%s: %s: No such file or directory\n",
argv[0], argv[i]);
error_occurred = 1;
}
}
for(c = fgetc(current_input_file); c != EOF;
c = fgetc(current_input_file)) {
if(using_unbuffered_output) {
write(1, &c, 1);
}
else {
fprintf(stdout, "%c", c);
}
}
fclose(current_input_file);
}
if(error_occurred) {
return 1; return 1;
else }
else {
return 0; return 0;
}
} }