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#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
static void
help_message(void) {
printf(
"chwrite [-h|--help]\n"
"chwrite +|+w|-|-w FILE...\n"
"\n"
"Change write permissions for file(s)\n"
);
}
int
main(int argc, char *argv[]) {
int i = 0, f = 0, result = 0;
struct stat fs = { 0, };
char operation;
if (argc <= 1) {
help_message();
return 0;
}
for (i = 1; i < argc; ++i) {
if (!strcmp(argv[i], "-h") || !strcmp(argv[i], "--help")) {
help_message();
return 0;
}
}
if (!strcmp(argv[1], "+") || !strcmp(argv[1], "+w")) {
operation = '+';
}
else if (!strcmp(argv[1], "-") || !strcmp(argv[1], "-w")) {
operation = '-';
}
else {
printf("Invalid argument '%s'!\n", argv[1]);
help_message();
return 1;
}
if (argc == 2) {
printf("Not enough arguments!\n");
help_message();
return 2;
}
for (i = 2; i < argc; ++i) {
f = open(argv[i], 0);
if (f == -1)
return errno;
result = fstat(f, &fs);
if (result == -1)
return errno;
if (operation == '+')
fs.st_mode |= S_IWUSR;
else
fs.st_mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
result = fchmod(f, fs.st_mode);
if (result == -1)
return errno;
}
return result;
}
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