xioctl and friends by Tito <farmatito@tiscali.it>

function                                             old     new   delta
do_iptunnel                                          203     977    +774
process_dev                                         5328    5494    +166
ioctl_or_perror                                        -      54     +54
ioctl_or_perror_and_die                                -      51     +51
ioctl_alt_func                                         -      49     +49
bb_ioctl_or_warn                                       -      47     +47
do_add_ioctl                                         102     145     +43
bb_xioctl                                              -      39     +39
print_value_on_off                                     -      31     +31
get_lcm                                              105     123     +18
arp_main                                            2155    2167     +12
..................
zcip_main                                           1576    1566     -10
setlogcons_main                                       92      82     -10
dumpkmap_main                                        263     253     -10
do_get_ioctl                                          85      75     -10
setkeycodes_main                                     165     154     -11
write_table                                          244     232     -12
vconfig_main                                         318     306     -12
do_del_ioctl                                          93      81     -12
set_address                                           75      62     -13
maybe_set_utc                                         30      16     -14
loadfont_main                                        495     479     -16
slattach_main                                        712     695     -17
do_loadfont                                          191     174     -17
do_iplink                                           1155    1136     -19
getty_main                                          2583    2562     -21
fbset_main                                          2058    2035     -23
do_time                                              588     565     -23
xioctl                                                25       -     -25
read_rtc                                             186     160     -26
parse_conf                                          1299    1270     -29
udhcp_read_interface                                 269     239     -30
bb_ioctl                                              45       -     -45
bb_ioctl_alt                                          70       -     -70
bb_ioctl_on_off                                       78       -     -78
.rodata                                           129370  129018    -352
do_show                                              799       -    -799
------------------------------------------------------------------------------
(add/remove: 6/5 grow/shrink: 13/49 up/down: 1316/-1864)     Total: -548 bytes
   text	   data	    bss	    dec	    hex	filename
 675352	   2740	  13968	 692060	  a8f5c	busybox_old
 674804	   2740	  13968	 691512	  a8d38	busybox_unstripped

15 files changed, 86 insertions, 136 deletions

diff --git a/networking/arp.c b/networking/arp.c
index 6a7c862b8..e529257a8 100644
--- a/networking/arp.c
+++ b/networking/arp.c
@@ -188,9 +188,8 @@ static void arp_getdevhw(char *ifname, struct sockaddr *sa,
 	const struct hwtype *xhw;
 
 	strcpy(ifr.ifr_name, ifname);
-	if (ioctl(sockfd, SIOCGIFHWADDR, &ifr) < 0) {
-		bb_perror_msg_and_die("cant get HW-Address for '%s'", ifname);
-	}
+	ioctl_or_perror_and_die(sockfd, SIOCGIFHWADDR, &ifr,
+					"cant get HW-Address for '%s'", ifname);
 	if (hwt && (ifr.ifr_hwaddr.sa_family != hw->type)) {
 		bb_error_msg_and_die("protocol type mismatch");
 	}
@@ -306,9 +305,7 @@ static int arp_set(char **args)
 	/* Call the kernel. */
 	if (option_mask32 & ARP_OPT_v)
 		bb_error_msg("SIOCSARP()");
-	if (ioctl(sockfd, SIOCSARP, &req) < 0) {
-		bb_perror_msg_and_die("SIOCSARP");
-	}
+	xioctl(sockfd, SIOCSARP, &req);
 	return 0;
 }
 
diff --git a/networking/arping.c b/networking/arping.c
index 7a9fbc2f4..8e457b13a 100644
--- a/networking/arping.c
+++ b/networking/arping.c
@@ -273,14 +273,11 @@ int arping_main(int argc, char **argv)
 
 		memset(&ifr, 0, sizeof(ifr));
 		strncpy(ifr.ifr_name, device, IFNAMSIZ - 1);
-		if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0) {
-			bb_error_msg_and_die("interface %s not found", device);
-		}
+		ioctl_or_perror_and_die(sock, SIOCGIFINDEX, &ifr, "interface %s not found", device);
 		ifindex = ifr.ifr_ifindex;
 
-		if (ioctl(sock, SIOCGIFFLAGS, (char *) &ifr)) {
-			bb_error_msg_and_die("SIOCGIFFLAGS");
-		}
+		xioctl(sock, SIOCGIFFLAGS, (char *) &ifr);
+
 		if (!(ifr.ifr_flags & IFF_UP)) {
 			bb_error_msg_and_die("interface %s is down", device);
 		}
diff --git a/networking/ether-wake.c b/networking/ether-wake.c
index 9de0d489b..b67e1b5d8 100644
--- a/networking/ether-wake.c
+++ b/networking/ether-wake.c
@@ -220,8 +220,7 @@ int ether_wake_main(int argc, char **argv)
 		struct ifreq if_hwaddr;
 
 		strncpy(if_hwaddr.ifr_name, ifname, sizeof(if_hwaddr.ifr_name));
-		if (ioctl(s, SIOCGIFHWADDR, &if_hwaddr) != 0)
-			bb_perror_msg_and_die("SIOCGIFHWADDR on %s failed", ifname);
+		ioctl_or_perror_and_die(s, SIOCGIFHWADDR, &if_hwaddr, "SIOCGIFHWADDR on %s failed", ifname);
 
 		memcpy(outpack+6, if_hwaddr.ifr_hwaddr.sa_data, 6);
 
@@ -257,8 +256,7 @@ int ether_wake_main(int argc, char **argv)
 	{
 		struct ifreq ifr;
 		strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
-		if (ioctl(s, SIOCGIFINDEX, &ifr) != 0)
-			bb_perror_msg_and_die("SIOCGIFINDEX");
+		xioctl(s, SIOCGIFINDEX, &ifr);
 		memset(&whereto, 0, sizeof(whereto));
 		whereto.sll_family = AF_PACKET;
 		whereto.sll_ifindex = ifr.ifr_ifindex;
diff --git a/networking/ifconfig.c b/networking/ifconfig.c
index 5e11b2b7c..0d53676cd 100644
--- a/networking/ifconfig.c
+++ b/networking/ifconfig.c
@@ -402,12 +402,10 @@ int ifconfig_main(int argc, char **argv)
 
 								/* Create a channel to the NET kernel. */
 								sockfd6 = xsocket(AF_INET6, SOCK_DGRAM, 0);
-								if (ioctl(sockfd6, SIOGIFINDEX, &ifr) < 0)
-									bb_perror_msg_and_die("SIOGIFINDEX");
+								xioctl(sockfd6, SIOGIFINDEX, &ifr);
 								ifr6.ifr6_ifindex = ifr.ifr_ifindex;
 								ifr6.ifr6_prefixlen = prefix_len;
-								if (ioctl(sockfd6, a1op->selector, &ifr6) < 0)
-									bb_perror_msg_and_die(a1op->name);
+								ioctl_or_perror_and_die(sockfd6, a1op->selector, &ifr6, "%s", a1op->name);
 								if (ENABLE_FEATURE_CLEAN_UP)
 									free(lsa);
 								continue;
@@ -444,8 +442,7 @@ int ifconfig_main(int argc, char **argv)
 					p = ((char *)&ifr) + a1op->ifr_offset;
 #if ENABLE_FEATURE_IFCONFIG_MEMSTART_IOADDR_IRQ
 					if (mask & A_MAP_TYPE) {
-						if (ioctl(sockfd, SIOCGIFMAP, &ifr) < 0)
-							bb_perror_msg_and_die("SIOCGIFMAP");
+						xioctl(sockfd, SIOCGIFMAP, &ifr);
 						if ((mask & A_MAP_UCHAR) == A_MAP_UCHAR)
 							*((unsigned char *) p) = i;
 						else if (mask & A_MAP_USHORT)
@@ -460,8 +457,7 @@ int ifconfig_main(int argc, char **argv)
 						*((int *) p) = i;
 				}
 
-				if (ioctl(sockfd, a1op->selector, &ifr) < 0)
-					bb_perror_msg_and_die(a1op->name);
+				ioctl_or_perror_and_die(sockfd, a1op->selector, &ifr, "%s", a1op->name);
 #ifdef QUESTIONABLE_ALIAS_CASE
 				if (mask & A_COLON_CHK) {
 					/*
@@ -486,15 +482,13 @@ int ifconfig_main(int argc, char **argv)
 			mask = N_SET;
 		}
 
-		if (ioctl(sockfd, SIOCGIFFLAGS, &ifr) < 0)
-			bb_perror_msg_and_die("SIOCGIFFLAGS");
+		xioctl(sockfd, SIOCGIFFLAGS, &ifr);
 		selector = op->selector;
 		if (mask & SET_MASK)
 			ifr.ifr_flags |= selector;
 		else
 			ifr.ifr_flags &= ~selector;
-		if (ioctl(sockfd, SIOCSIFFLAGS, &ifr) < 0)
-			bb_perror_msg_and_die("SIOCSIFFLAGS");
+		xioctl(sockfd, SIOCSIFFLAGS, &ifr);
 	} /* while () */
 
 	if (ENABLE_FEATURE_CLEAN_UP)
diff --git a/networking/interface.c b/networking/interface.c
index 204febf7d..ea02f4cc9 100644
--- a/networking/interface.c
+++ b/networking/interface.c
@@ -521,8 +521,7 @@ static int if_readconf(void)
 		ifc.ifc_len = sizeof(struct ifreq) * numreqs;
 		ifc.ifc_buf = xrealloc(ifc.ifc_buf, ifc.ifc_len);
 
-		if (ioctl(skfd, SIOCGIFCONF, &ifc) < 0) {
-			bb_perror_msg("SIOCGIFCONF");
+		if (ioctl_or_warn(skfd, SIOCGIFCONF, &ifc) < 0) {
 			goto out;
 		}
 		if (ifc.ifc_len == sizeof(struct ifreq) * numreqs) {
diff --git a/networking/libiproute/ipaddress.c b/networking/libiproute/ipaddress.c
index a4add6a47..fc10ba37c 100644
--- a/networking/libiproute/ipaddress.c
+++ b/networking/libiproute/ipaddress.c
@@ -84,8 +84,7 @@ static void print_queuelen(char *name)
 
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
-	if (ioctl(s, SIOCGIFTXQLEN, &ifr) < 0) {
-		bb_perror_msg("SIOCGIFXQLEN");
+	if (ioctl_or_warn(s, SIOCGIFTXQLEN, &ifr) < 0) {
 		close(s);
 		return;
 	}
diff --git a/networking/libiproute/iplink.c b/networking/libiproute/iplink.c
index 7db4d7e15..3d3ea2a23 100644
--- a/networking/libiproute/iplink.c
+++ b/networking/libiproute/iplink.c
@@ -49,14 +49,11 @@ static void do_chflags(char *dev, uint32_t flags, uint32_t mask)
 
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	fd = get_ctl_fd();
-	if (ioctl(fd, SIOCGIFFLAGS, &ifr)) {
-		bb_perror_msg_and_die("SIOCGIFFLAGS");
-	}
+	xioctl(fd, SIOCGIFFLAGS, &ifr);
 	if ((ifr.ifr_flags ^ flags) & mask) {
 		ifr.ifr_flags &= ~mask;
 		ifr.ifr_flags |= mask & flags;
-		if (ioctl(fd, SIOCSIFFLAGS, &ifr))
-			bb_perror_msg_and_die("SIOCSIFFLAGS");
+		xioctl(fd, SIOCSIFFLAGS, &ifr);
 	}
 	close(fd);
 }
@@ -66,15 +63,11 @@ static void do_changename(char *dev, char *newdev)
 {
 	struct ifreq ifr;
 	int fd;
-	int err;
 
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	strncpy(ifr.ifr_newname, newdev, sizeof(ifr.ifr_newname));
 	fd = get_ctl_fd();
-	err = ioctl(fd, SIOCSIFNAME, &ifr);
-	if (err) {
-		bb_perror_msg_and_die("SIOCSIFNAME");
-	}
+	xioctl(fd, SIOCSIFNAME, &ifr);
 	close(fd);
 }
 
@@ -88,9 +81,7 @@ static void set_qlen(char *dev, int qlen)
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	ifr.ifr_qlen = qlen;
-	if (ioctl(s, SIOCSIFTXQLEN, &ifr) < 0) {
-		bb_perror_msg_and_die("SIOCSIFXQLEN");
-	}
+	xioctl(s, SIOCSIFTXQLEN, &ifr);
 	close(s);
 }
 
@@ -104,9 +95,7 @@ static void set_mtu(char *dev, int mtu)
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	ifr.ifr_mtu = mtu;
-	if (ioctl(s, SIOCSIFMTU, &ifr) < 0) {
-		bb_perror_msg_and_die("SIOCSIFMTU");
-	}
+	xioctl(s, SIOCSIFMTU, &ifr);
 	close(s);
 }
 
@@ -122,9 +111,7 @@ static int get_address(char *dev, int *htype)
 
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
-	if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
-		bb_perror_msg_and_die("SIOCGIFINDEX");
-	}
+	xioctl(s, SIOCGIFINDEX, &ifr);
 
 	memset(&me, 0, sizeof(me));
 	me.sll_family = AF_PACKET;
@@ -163,9 +150,10 @@ static void set_address(struct ifreq *ifr, int brd)
 	int s;
 
 	s = get_ctl_fd();
-	if (ioctl(s, brd ? SIOCSIFHWBROADCAST  :SIOCSIFHWADDR, ifr) < 0) {
-		bb_perror_msg_and_die(brd ? "SIOCSIFHWBROADCAST" : "SIOCSIFHWADDR");
-	}
+	if (brd)
+		xioctl(s, SIOCSIFHWBROADCAST, ifr);
+	else
+		xioctl(s, SIOCSIFHWADDR, ifr);
 	close(s);
 }
 
diff --git a/networking/libiproute/iptunnel.c b/networking/libiproute/iptunnel.c
index b12bceb45..90d0e1186 100644
--- a/networking/libiproute/iptunnel.c
+++ b/networking/libiproute/iptunnel.c
@@ -14,8 +14,6 @@
  * Phil Karn <karn@ka9q.ampr.org>	990408:	"pmtudisc" flag
  */
 
-//#include <sys/socket.h>
-//#include <sys/ioctl.h>
 #include <netinet/ip.h>
 #include <net/if.h>
 #include <net/if_arp.h>
@@ -38,9 +36,7 @@ static int do_ioctl_get_ifindex(char *dev)
 
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
-	if (ioctl(fd, SIOCGIFINDEX, &ifr)) {
-		bb_perror_msg_and_die("SIOCGIFINDEX");
-	}
+	xioctl(fd, SIOCGIFINDEX, &ifr);
 	close(fd);
 	return ifr.ifr_ifindex;
 }
@@ -49,30 +45,26 @@ static int do_ioctl_get_iftype(char *dev)
 {
 	struct ifreq ifr;
 	int fd;
+	int err;
 
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
-	if (ioctl(fd, SIOCGIFHWADDR, &ifr)) {
-		bb_perror_msg("SIOCGIFHWADDR");
-		return -1;
-	}
+	err = ioctl_or_warn(fd, SIOCGIFHWADDR, &ifr);
 	close(fd);
-	return ifr.ifr_addr.sa_family;
+	return err ? -1 : ifr.ifr_addr.sa_family;
 }
 
 static char *do_ioctl_get_ifname(int idx)
 {
 	struct ifreq ifr;
 	int fd;
+	int err;
 
 	ifr.ifr_ifindex = idx;
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
-	if (ioctl(fd, SIOCGIFNAME, &ifr)) {
-		bb_perror_msg("SIOCGIFNAME");
-		return NULL;
-	}
+	err = ioctl_or_warn(fd, SIOCGIFNAME, &ifr);
 	close(fd);
-	return xstrndup(ifr.ifr_name, sizeof(ifr.ifr_name));
+	return err ? NULL : xstrndup(ifr.ifr_name, sizeof(ifr.ifr_name));
 }
 
 static int do_get_ioctl(const char *basedev, struct ip_tunnel_parm *p)
@@ -84,10 +76,7 @@ static int do_get_ioctl(const char *basedev, struct ip_tunnel_parm *p)
 	strncpy(ifr.ifr_name, basedev, sizeof(ifr.ifr_name));
 	ifr.ifr_ifru.ifru_data = (void*)p;
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
-	err = ioctl(fd, SIOCGETTUNNEL, &ifr);
-	if (err) {
-		bb_perror_msg("SIOCGETTUNNEL");
-	}
+	err = ioctl_or_warn(fd, SIOCGETTUNNEL, &ifr);
 	close(fd);
 	return err;
 }
@@ -105,9 +94,15 @@ static int do_add_ioctl(int cmd, const char *basedev, struct ip_tunnel_parm *p)
 	}
 	ifr.ifr_ifru.ifru_data = (void*)p;
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
-	if (ioctl(fd, cmd, &ifr)) {
-		bb_perror_msg_and_die("ioctl");
-	}
+#if ENABLE_IOCTL_HEX2STR_ERROR
+	/* #define magic will turn ioctl# into string */
+	if (cmd == SIOCCHGTUNNEL)
+		xioctl(fd, SIOCCHGTUNNEL, &ifr);
+	else
+		xioctl(fd, SIOCADDTUNNEL, &ifr);
+#else
+	xioctl(fd, cmd, &ifr);
+#endif
 	close(fd);
 	return 0;
 }
@@ -125,9 +120,7 @@ static int do_del_ioctl(const char *basedev, struct ip_tunnel_parm *p)
 	}
 	ifr.ifr_ifru.ifru_data = (void*)p;
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
-	if (ioctl(fd, SIOCDELTUNNEL, &ifr)) {
-		bb_perror_msg_and_die("SIOCDELTUNNEL");
-	}
+	xioctl(fd, SIOCDELTUNNEL, &ifr);
 	close(fd);
 	return 0;
 }
@@ -526,29 +519,24 @@ static int do_show(int argc, char **argv)
 /* Return value becomes exitcode. It's okay to not return at all */
 int do_iptunnel(int argc, char **argv)
 {
-	static const char * const keywords[] = {
+	static const char *const keywords[] = {
 		"add", "change", "delete", "show", "list", "lst", NULL
 	};
-	enum {ARG_add = 1, ARG_change, ARG_del, ARG_show, ARG_list, ARG_lst};
-	smalluint key = 4; /* show */
-	if (argc > 0) {
-		key = index_in_substr_array(keywords, *argv) +1;
+	enum { ARG_add = 0, ARG_change, ARG_del, ARG_show, ARG_list, ARG_lst };
+	int key;
+
+	if (argc) {
+		key = index_in_substr_array(keywords, *argv);
+		if (key < 0)
+			bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
 		--argc;
 		++argv;
-	} else
-		return do_show(0, NULL);
-	if (key < ARG_add)
- bail:
-		bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
-
-	if (key == ARG_add)
-		return do_add(SIOCADDTUNNEL, argc, argv);
-	if (key == ARG_change)
-		return do_add(SIOCCHGTUNNEL, argc, argv);
-	if (key == ARG_del)
-		return do_del(argc, argv);
-	if (key == ARG_show || key == ARG_list || key == ARG_lst)
-		return do_show(argc, argv);
-	/* be gentle to gcc; avoid warning about non returning */
-	goto bail; /* never reached */
+		if (key == ARG_add)
+			return do_add(SIOCADDTUNNEL, argc, argv);
+		if (key == ARG_change)
+			return do_add(SIOCCHGTUNNEL, argc, argv);
+		if (key == ARG_del)
+			return do_del(argc, argv);
+	}
+	return do_show(argc, argv);
 }
diff --git a/networking/nameif.c b/networking/nameif.c
index a65f30819..fd081fd63 100644
--- a/networking/nameif.c
+++ b/networking/nameif.c
@@ -148,9 +148,9 @@ int nameif_main(int argc, char **argv)
 			continue;
 
 		strcpy(ifr.ifr_newname, ch->ifname);
-		if (ioctl(ctl_sk, SIOCSIFNAME, &ifr) < 0)
-			bb_perror_msg_and_die("cannot change ifname %s to %s",
-				   ifr.ifr_name, ch->ifname);
+		ioctl_or_perror_and_die(ctl_sk, SIOCSIFNAME, &ifr,
+					"cannot change ifname %s to %s",
+					ifr.ifr_name, ch->ifname);
 
 		/* Remove list entry of renamed interface */
 		if (ch->prev != NULL) {
diff --git a/networking/route.c b/networking/route.c
index b5490ddd8..530c51b10 100644
--- a/networking/route.c
+++ b/networking/route.c
@@ -327,9 +327,10 @@ static void INET_setroute(int action, char **args)
 	/* Create a socket to the INET kernel. */
 	skfd = xsocket(AF_INET, SOCK_DGRAM, 0);
 
-	if (ioctl(skfd, ((action==RTACTION_ADD) ? SIOCADDRT : SIOCDELRT), &rt)<0) {
-		bb_perror_msg_and_die("SIOC[ADD|DEL]RT");
-	}
+	if (action == RTACTION_ADD)
+		xioctl(skfd, SIOCADDRT, &rt);
+	else
+		xioctl(skfd, SIOCDELRT, &rt);
 
 	if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
 }
@@ -423,17 +424,15 @@ static void INET6_setroute(int action, char **args)
 		struct ifreq ifr;
 		memset(&ifr, 0, sizeof(ifr));
 		strncpy(ifr.ifr_name, devname, sizeof(ifr.ifr_name));
-
-		if (ioctl(skfd, SIOGIFINDEX, &ifr) < 0) {
-			bb_perror_msg_and_die("SIOGIFINDEX");
-		}
+		xioctl(skfd, SIOGIFINDEX, &ifr);
 		rt.rtmsg_ifindex = ifr.ifr_ifindex;
 	}
 
 	/* Tell the kernel to accept this route. */
-	if (ioctl(skfd, ((action==RTACTION_ADD) ? SIOCADDRT : SIOCDELRT), &rt)<0) {
-		bb_perror_msg_and_die("SIOC[ADD|DEL]RT");
-	}
+	if (action == RTACTION_ADD)
+		xioctl(skfd, SIOCADDRT, &rt);
+	else
+		xioctl(skfd, SIOCDELRT, &rt);
 
 	if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
 }
diff --git a/networking/slattach.c b/networking/slattach.c
index 3495df598..1a4423b72 100644
--- a/networking/slattach.c
+++ b/networking/slattach.c
@@ -50,8 +50,7 @@ static void save_state(void)
 		bb_perror_msg_and_die("get state");
 
 	/* Save line discipline */
-	if (ioctl(handle, TIOCGETD, &saved_disc) < 0)
-		bb_perror_msg_and_die("get discipline");
+	xioctl(handle, TIOCGETD, &saved_disc);
 }
 
 static int set_termios_state_and_warn(struct termios *state)
@@ -81,8 +80,7 @@ static void restore_state_and_exit(int exitcode)
 	struct termios state;
 
 	/* Restore line discipline */
-	if (ioctl(handle, TIOCSETD, &saved_disc) < 0) {
-		bb_perror_msg("set discipline");
+	if (ioctl_or_warn(handle, TIOCSETD, &saved_disc) < 0) {
 		exitcode = 1;
 	}
 
@@ -115,14 +113,12 @@ static void set_state(struct termios *state, int encap)
 		goto bad;
 	/* Set line discliple (N_SLIP always) */
 	disc = N_SLIP;
-	if (ioctl(handle, TIOCSETD, &disc) < 0) {
-		bb_perror_msg("set discipline");
+	if (ioctl_or_warn(handle, TIOCSETD, &disc) < 0) {
 		goto bad;
 	}
 
 	/* Set encapsulation (SLIP, CSLIP, etc) */
-	if (ioctl(handle, SIOCSIFENCAP, &encap) < 0) {
-		bb_perror_msg("set encapsulation");
+	if (ioctl_or_warn(handle, SIOCSIFENCAP, &encap) < 0) {
  bad:
 		restore_state_and_exit(1);
 	}
diff --git a/networking/traceroute.c b/networking/traceroute.c
index ad3ec4eda..c87f7ffc5 100644
--- a/networking/traceroute.c
+++ b/networking/traceroute.c
@@ -445,8 +445,8 @@ ifaddrlist(struct IFADDRLIST **ipaddrp)
 		if (strchr(al->device, ':') != NULL)
 			continue;
 #endif
-		if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0)
-			bb_perror_msg_and_die("SIOCGIFADDR: %s", al->device);
+		ioctl_or_perror_and_die(fd, SIOCGIFADDR, (char *)&ifr,
+				"SIOCGIFADDR: %s", al->device);
 
 		addr_sin = (struct sockaddr_in *)&ifr.ifr_addr;
 		al->addr = addr_sin->sin_addr.s_addr;
diff --git a/networking/udhcp/socket.c b/networking/udhcp/socket.c
index be5985f88..21a058545 100644
--- a/networking/udhcp/socket.c
+++ b/networking/udhcp/socket.c
@@ -53,9 +53,9 @@ int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t
 	ifr.ifr_addr.sa_family = AF_INET;
 	strncpy(ifr.ifr_name, interface, sizeof(ifr.ifr_name));
 	if (addr) {
-		if (ioctl(fd, SIOCGIFADDR, &ifr) != 0) {
-			bb_perror_msg("SIOCGIFADDR failed (is interface %s "
-					"up and configured?)", interface);
+		if (ioctl_or_perror(fd, SIOCGIFADDR, &ifr, 
+			"is interface %s up and configured?", interface)
+		) {
 			close(fd);
 			return -1;
 		}
@@ -65,8 +65,7 @@ int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t
 	}
 
 	if (ifindex) {
-		if (ioctl(fd, SIOCGIFINDEX, &ifr) != 0) {
-			bb_perror_msg("SIOCGIFINDEX failed");
+		if (ioctl_or_warn(fd, SIOCGIFINDEX, &ifr) != 0) {
 			close(fd);
 			return -1;
 		}
@@ -75,8 +74,7 @@ int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t
 	}
 
 	if (arp) {
-		if (ioctl(fd, SIOCGIFHWADDR, &ifr) != 0) {
-			bb_perror_msg("SIOCGIFHWADDR failed");
+		if (ioctl_or_warn(fd, SIOCGIFHWADDR, &ifr) != 0) {
 			close(fd);
 			return -1;
 		}
diff --git a/networking/vconfig.c b/networking/vconfig.c
index e063d0a49..4776e1324 100644
--- a/networking/vconfig.c
+++ b/networking/vconfig.c
@@ -157,9 +157,8 @@ int vconfig_main(int argc, char **argv)
 	}
 
 	fd = xsocket(AF_INET, SOCK_STREAM, 0);
-	if (ioctl(fd, SIOCSIFVLAN, &ifr) < 0) {
-		bb_perror_msg_and_die("ioctl error for %s", *argv);
-	}
+	ioctl_or_perror_and_die(fd, SIOCSIFVLAN, &ifr,
+						"ioctl error for %s", *argv);
 
 	return 0;
 }
diff --git a/networking/zcip.c b/networking/zcip.c
index de4ee0b1a..281f551d7 100644
--- a/networking/zcip.c
+++ b/networking/zcip.c
@@ -247,9 +247,7 @@ int zcip_main(int argc, char **argv)
 	// get the interface's ethernet address
 	//memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, intf, sizeof(ifr.ifr_name));
-	if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
-		bb_perror_msg_and_die("get ethernet address");
-	}
+	xioctl(fd, SIOCGIFHWADDR, &ifr);
 	memcpy(&eth_addr, &ifr.ifr_hwaddr.sa_data, ETH_ALEN);
 
 	// start with some stable ip address, either a function of