Add pwdx(1)

Signed-off-by: Mattias Andrée <maandree@kth.se>

Makefile

@@ -70,6 +70,7 @@ BIN = \
 	pidof             \
 	pivot_root        \
 	ps                \
+	pwdx              \
 	readahead         \
 	respawn           \
 	rmmod             \
@@ -106,6 +107,7 @@ MAN1 = \
 	passwd.1            \
 	pidof.1             \
 	ps.1                \
+	pwdx.1              \
 	respawn.1           \
 	stat.1              \
 	su.1                \

TODO

@@ -19,7 +19,6 @@ mkswap [-L]
 partprobe
 pmap
 ps (support for more options)
-pwdx
 rfkill
 rmgroup
 rmuser

pwdx.1

@@ -0,0 +1,13 @@
+.Dd March 26, 2015
+.Dt PWDX 1
+.Os ubase
+.Sh NAME
+.Nm pwdx
+.Nd print working directory of other processes
+.Sh SYNOPSIS
+.Nm
+.Ar pid...
+.Sh DESCRIPTION
+.Nm
+Prints the current working directory for each
+.Ar pid .

pwdx.c

@@ -0,0 +1,51 @@
+/* See LICENSE file for copyright and license details. */
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "util.h"
+
+static void
+usage(void)
+{
+	eprintf("usage: %s pid...\n", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	int ret = 0;
+	char path[PATH_MAX];
+	char target[PATH_MAX + sizeof(" (deleted)")];
+	ssize_t n;
+
+	ARGBEGIN {
+	default:
+		usage();
+	} ARGEND;
+
+	if (argc == 0)
+		usage();
+
+	for (; argc > 0; argc--, argv++) {
+		n = snprintf(path, sizeof(path), "/proc/%s/cwd", *argv);
+		if (n < 0 || n > sizeof(path)) {
+			errno = ESRCH;
+		} else {
+			n = readlink(path, target, sizeof(target) - 1);
+			if (n >= 0) {
+				target[n] = '\0';
+				printf("%s: %s\n", *argv, target);
+				continue;
+			}
+		}
+		if (errno == ENOENT)
+			errno = ESRCH;
+		weprintf("%s:", *argv);
+		ret = 1;
+	}
+
+	return ret;
+}