From 0226c051056e873d7faa46434b1b012eac59af12 Mon Sep 17 00:00:00 2001
From: FRIGN <dev@frign.de>
Date: Sat, 28 Feb 2015 21:47:17 +0100
Subject: [PATCH] Audit printenv(1)

1) argc style
2) safeguard argv-loop as already seen in echo(1) with argc-decrement.
---
 README     | 2 +-
 echo.c     | 2 +-
 printenv.c | 9 +++++----
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/README b/README
index 4a2d7a2..7bccbf6 100644
--- a/README
+++ b/README
@@ -51,7 +51,7 @@ The following tools are implemented ('*' == finished, '#' == UTF-8 support,
 =   nl              no                           -d, -f, -h, -l, -p
 =*  nohup           yes                          none
 #*  paste           yes                          none
-=*  printenv        non-posix                    none
+=*| printenv        non-posix                    none
 #*  printf          yes                          none
 =*  pwd             yes                          none
 =   readlink        non-posix                    none
diff --git a/echo.c b/echo.c
index 2ae8af9..8b58bcc 100644
--- a/echo.c
+++ b/echo.c
@@ -23,7 +23,7 @@ main(int argc, char *argv[])
 	} ARGEND;
 
 	for (; argc > 0; argc--, argv++)
-		putword(argv[0]);
+		putword(*argv);
 	if (!nflag)
 		putchar('\n');
 
diff --git a/printenv.c b/printenv.c
index 675a6f9..ff210cb 100644
--- a/printenv.c
+++ b/printenv.c
@@ -9,7 +9,7 @@ extern char **environ;
 static void
 usage(void)
 {
-	eprintf("usage: %s [variable...]\n", argv0);
+	eprintf("usage: %s [var ...]\n", argv0);
 }
 
 int
@@ -23,16 +23,17 @@ main(int argc, char *argv[])
 		usage();
 	} ARGEND;
 
-	if (argc == 0) {
+	if (!argc) {
 		while (*environ)
 			printf("%s\n", *environ++);
 	} else {
-		while (*argv) {
-			if ((var = getenv(*argv++)))
+		for (; argc > 0; argc--, argv++) {
+			if ((var = getenv(*argv)))
 				printf("%s\n", var);
 			else
 				ret = 1;
 		}
 	}
+
 	return ret;
 }