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#include "stddef.h"
#include <err.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <unistd.h>
int main(int argc, char **argv)
{
const char *out = NULL;
struct iovec iov[2];
char opt, mode = 'L';
char cwd[PATH_MAX];
while ((opt = getopt(argc, argv, "")) != -1) {
switch (opt) {
case 'L':
case 'P':
mode = opt;
break;
default:
write(STDERR_FILENO, "usage: pwd [-L|-P]\n", 20);
return 1;
}
}
if (getcwd(cwd, sizeof(cwd)) == NULL) {
perror("pwd: getcwd");
return 1;
}
if (mode == 'L') {
const char *pwd;
struct stat cst, pst;
if ((pwd = getenv("PWD")) == NULL || *pwd != '/' ||
stat(pwd, &pst) < 0) {
out = cwd;
}
if (stat(cwd, &cst) < 0) {
perror("pwd: stat");
}
out = (pst.st_dev == cst.st_dev && pst.st_ino == cst.st_ino) ?
pwd :
cwd;
}
iov[0].iov_base = (char *)out;
iov[0].iov_len = strlen(out);
iov[1].iov_base = "\n";
iov[1].iov_len = 1;
if (writev(STDOUT_FILENO, iov, 2) < 0) {
err(1, "pwd");
}
return 0;
}
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