diff --git a/cat.c b/cat.c
index 90eefd5..1890e49 100644
--- a/cat.c
+++ b/cat.c
@@ -28,7 +28,7 @@ main(int argc, char *argv[])
 	if (argc == 0) {
 		concat(stdin, "<stdin>", stdout, "<stdout>");
 	} else {
-		for (; argc > 0; argc--, argv++) {
+		for (; *argv; argc--, argv++) {
 			if ((*argv)[0] == '-' && !(*argv)[1]) {
 				concat(stdin, "<stdin>", stdout, "<stdout>");
 			} else if (!(fp = fopen(*argv, "r"))) {
diff --git a/echo.c b/echo.c
index 8b58bcc..8280137 100644
--- a/echo.c
+++ b/echo.c
@@ -22,7 +22,7 @@ main(int argc, char *argv[])
 		usage();
 	} ARGEND;
 
-	for (; argc > 0; argc--, argv++)
+	for (; *argv; argc--, argv++)
 		putword(*argv);
 	if (!nflag)
 		putchar('\n');
diff --git a/libutil/crypt.c b/libutil/crypt.c
index 9237cc5..91f80e6 100644
--- a/libutil/crypt.c
+++ b/libutil/crypt.c
@@ -87,7 +87,7 @@ cryptcheck(int argc, char *argv[], struct crypt_ops *ops, uint8_t *md, size_t sz
 	if (argc == 0) {
 		mdchecklist(stdin, ops, md, sz, &formatsucks, &noread, &nonmatch);
 	} else {
-		for (; argc > 0; argc--, argv++) {
+		for (; *argv; argc--, argv++) {
 			if (!(fp = fopen(*argv, "r"))) {
 				weprintf("fopen %s:", *argv);
 				ret = 1;
@@ -124,7 +124,7 @@ cryptmain(int argc, char *argv[], struct crypt_ops *ops, uint8_t *md, size_t sz)
 		cryptsum(ops, stdin, "<stdin>", md);
 		mdprint(md, "<stdin>", sz);
 	} else {
-		for (; argc > 0; argc--, argv++) {
+		for (; *argv; argc--, argv++) {
 			if (!(fp = fopen(*argv, "r"))) {
 				weprintf("fopen %s:", *argv);
 				ret = 1;
diff --git a/printenv.c b/printenv.c
index ff210cb..135e0e3 100644
--- a/printenv.c
+++ b/printenv.c
@@ -24,12 +24,12 @@ main(int argc, char *argv[])
 	} ARGEND;
 
 	if (!argc) {
-		while (*environ)
-			printf("%s\n", *environ++);
+		for (; *environ; environ++)
+			puts(*environ);
 	} else {
-		for (; argc > 0; argc--, argv++) {
+		for (; *argv; argc--, argv++) {
 			if ((var = getenv(*argv)))
-				printf("%s\n", var);
+				puts(var);
 			else
 				ret = 1;
 		}
diff --git a/rm.c b/rm.c
index 73f3c31..3b539e6 100644
--- a/rm.c
+++ b/rm.c
@@ -30,8 +30,8 @@ main(int argc, char *argv[])
 			return 0;
 	}
 
-	for (; argc > 0; argc--, argv++)
-		rm(argv[0], 0);
+	for (; *argv; argc--, argv++)
+		rm(*argv, 0);
 
 	return rm_status;
 }
diff --git a/yes.c b/yes.c
index eddc0f0..000f367 100644
--- a/yes.c
+++ b/yes.c
@@ -12,16 +12,16 @@ usage(void)
 int
 main(int argc, char *argv[])
 {
-	size_t i;
+	char **p;
 
 	ARGBEGIN {
 	default:
 		usage();
 	} ARGEND;
 
-	for (i = 0; ; i++, i %= argc ? argc : 1) {
-		fputs(argc ? argv[i] : "y", stdout);
-		putchar((!argc || i == argc - 1) ? '\n' : ' ');
+	for (p = argv; ; p = (*p && *(p + 1)) ? p + 1 : argv) {
+		fputs(*p ? *p : "y", stdout);
+		putchar((!*p || !*(p + 1)) ? '\n' : ' ');
 	}
 
 	return 1; /* not reached */