Add some PCAP_WARNING return values for "success, but you might want to

know that..."; currently, only pcap_activate() returns them, but we
might want some more warning returns for some other calls, such as the
ones that set filters.  It's a little cleaner than "clear out the error
message buffer and, if it's not empty after a successful return, it has
a warning", and a little cleaner than spewing a warning to the standard
error (as that might not be visible to the user if they're running a GUI
application).

pcap-bpf.c

@@ -20,7 +20,7 @@
  */
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/libpcap/pcap-bpf.c,v 1.107 2008-04-09 19:58:02 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/pcap-bpf.c,v 1.108 2008-04-09 21:26:12 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -1028,7 +1028,7 @@ check_setif_failure(pcap_t *p, int error)
 static int
 pcap_activate_bpf(pcap_t *p)
 {
-	int err;
+	int status = 0;
 	int fd;
 	struct ifreq ifr;
 	struct bpf_version bv;
@@ -1053,7 +1053,7 @@ pcap_activate_bpf(pcap_t *p)
 
 	fd = bpf_open(p);
 	if (fd < 0) {
-		err = fd;
+		status = fd;
 		goto bad;
 	}
 
@@ -1062,14 +1062,14 @@ pcap_activate_bpf(pcap_t *p)
 	if (ioctl(fd, BIOCVERSION, (caddr_t)&bv) < 0) {
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCVERSION: %s",
 		    pcap_strerror(errno));
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 	if (bv.bv_major != BPF_MAJOR_VERSION ||
 	    bv.bv_minor < BPF_MINOR_VERSION) {
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 		    "kernel bpf filter out of date");
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 
@@ -1102,7 +1102,7 @@ pcap_activate_bpf(pcap_t *p)
 				/*
 				 * 10.3 (Darwin 7.x) or earlier.
 				 */
-				err = PCAP_ERROR_RFMON_NOTSUP;
+				status = PCAP_ERROR_RFMON_NOTSUP;
 				goto bad;
 			}
 			if (osinfo.release[0] == '8' &&
@@ -1129,10 +1129,10 @@ pcap_activate_bpf(pcap_t *p)
 							 * device doesn't
 							 * exist.
 							 */
-							err = PCAP_ERROR_NO_SUCH_DEVICE;
+							status = PCAP_ERROR_NO_SUCH_DEVICE;
 							strcpy(p->errbuf, "");
 						} else
-							err = PCAP_ERROR_RFMON_NOTSUP;
+							status = PCAP_ERROR_RFMON_NOTSUP;
 						close(sockfd);
 					} else {
 						/*
@@ -1140,7 +1140,7 @@ pcap_activate_bpf(pcap_t *p)
 						 * the device exists, so just
 						 * report "no such device".
 						 */
-						err = PCAP_ERROR_NO_SUCH_DEVICE;
+						status = PCAP_ERROR_NO_SUCH_DEVICE;
 						strcpy(p->errbuf, "");
 					}
 					goto bad;
@@ -1150,7 +1150,7 @@ pcap_activate_bpf(pcap_t *p)
 					(void)snprintf(p->errbuf,
 					    PCAP_ERRBUF_SIZE, "malloc: %s",
 					    pcap_strerror(errno));
-					err = PCAP_ERROR;
+					status = PCAP_ERROR;
 					goto bad;
 				}
 				strcpy(wltdev, "wlt");
@@ -1177,7 +1177,7 @@ pcap_activate_bpf(pcap_t *p)
 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 			    "BIOCSBLEN: %s: %s", p->opt.source,
 			    pcap_strerror(errno));
-			err = PCAP_ERROR;
+			status = PCAP_ERROR;
 			goto bad;
 		}
 
@@ -1187,7 +1187,7 @@ pcap_activate_bpf(pcap_t *p)
 		(void)strncpy(ifr.ifr_name, p->opt.source,
 		    sizeof(ifr.ifr_name));
 		if (ioctl(fd, BIOCSETIF, (caddr_t)&ifr) < 0) {
-			err = check_setif_failure(p, errno);
+			status = check_setif_failure(p, errno);
 			goto bad;
 		}
 	} else {
@@ -1217,7 +1217,7 @@ pcap_activate_bpf(pcap_t *p)
 				break;	/* that size worked; we're done */
 
 			if (errno != ENOBUFS) {
-				err = check_setif_failure(p, errno);
+				status = check_setif_failure(p, errno);
 				goto bad;
 			}
 		}
@@ -1226,7 +1226,7 @@ pcap_activate_bpf(pcap_t *p)
 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 			    "BIOCSBLEN: %s: No buffer size worked",
 			    p->opt.source);
-			err = PCAP_ERROR;
+			status = PCAP_ERROR;
 			goto bad;
 		}
 	}
@@ -1235,7 +1235,7 @@ pcap_activate_bpf(pcap_t *p)
 	if (ioctl(fd, BIOCGDLT, (caddr_t)&v) < 0) {
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGDLT: %s",
 		    pcap_strerror(errno));
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 
@@ -1268,7 +1268,7 @@ pcap_activate_bpf(pcap_t *p)
 		 */
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "unknown interface type %u",
 		    v);
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 #endif
@@ -1301,7 +1301,7 @@ pcap_activate_bpf(pcap_t *p)
 	 * not fatal; we just don't get to use the feature later.
 	 */
 	if (get_dlt_list(fd, v, &bdl, p->errbuf) == -1) {
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 	p->dlt_count = bdl.bfl_len;
@@ -1386,7 +1386,7 @@ pcap_activate_bpf(pcap_t *p)
 					 * link-layer types, so they
 					 * can't have it.
 					 */
-					err = PCAP_ERROR_RFMON_NOTSUP;
+					status = PCAP_ERROR_RFMON_NOTSUP;
 					goto bad;
 				}
 			}
@@ -1401,8 +1401,8 @@ pcap_activate_bpf(pcap_t *p)
 		/*
 		 * Try to put the interface into monitor mode.
 		 */
-		err = monitor_mode(p, 1);
-		if (err != 0) {
+		status = monitor_mode(p, 1);
+		if (status != 0) {
 			/*
 			 * We failed.
 			 */
@@ -1479,7 +1479,7 @@ pcap_activate_bpf(pcap_t *p)
 	if (ioctl(fd, BIOCSHDRCMPLT, &spoof_eth_src) == -1) {
 		(void)snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 		    "BIOCSHDRCMPLT: %s", pcap_strerror(errno));
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 #endif
@@ -1496,7 +1496,7 @@ pcap_activate_bpf(pcap_t *p)
 		if (ioctl(p->fd, BIOCSRTIMEOUT, (caddr_t)&to) < 0) {
 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSRTIMEOUT: %s",
 			    pcap_strerror(errno));
-			err = PCAP_ERROR;
+			status = PCAP_ERROR;
 			goto bad;
 		}
 	}
@@ -1553,7 +1553,7 @@ pcap_activate_bpf(pcap_t *p)
 	if (ioctl(p->fd, BIOCIMMEDIATE, &v) < 0) {
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCIMMEDIATE: %s",
 		    pcap_strerror(errno));
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 #endif	/* BIOCIMMEDIATE */
@@ -1564,13 +1564,14 @@ pcap_activate_bpf(pcap_t *p)
 		if (ioctl(p->fd, BIOCPROMISC, NULL) < 0) {
 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCPROMISC: %s",
 			    pcap_strerror(errno));
+			status = PCAP_WARNING_PROMISC_NOTSUP;
 		}
 	}
 
 	if (ioctl(fd, BIOCGBLEN, (caddr_t)&v) < 0) {
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGBLEN: %s",
 		    pcap_strerror(errno));
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 	p->bufsize = v;
@@ -1578,7 +1579,7 @@ pcap_activate_bpf(pcap_t *p)
 	if (p->buffer == NULL) {
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "malloc: %s",
 		    pcap_strerror(errno));
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 #ifdef _AIX
@@ -1606,7 +1607,7 @@ pcap_activate_bpf(pcap_t *p)
 	if (ioctl(p->fd, BIOCSETF, (caddr_t)&total_prog) < 0) {
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETF: %s",
 		    pcap_strerror(errno));
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto bad;
 	}
 
@@ -1668,14 +1669,14 @@ pcap_activate_bpf(pcap_t *p)
 	p->stats_op = pcap_stats_bpf;
 	p->close_op = pcap_close_bpf;
 
-	return (0);
+	return (status);
  bad:
 	(void)close(fd);
 	if (p->buffer != NULL) {
 		free(p->buffer);
 		p->buffer = NULL;
 	}
-	return (err);
+	return (status);
 }
 
 int

pcap-dlpi.c

@@ -70,7 +70,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/libpcap/pcap-dlpi.c,v 1.123 2008-04-09 19:58:02 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/pcap-dlpi.c,v 1.124 2008-04-09 21:26:12 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -342,7 +342,7 @@ pcap_activate_dlpi(pcap_t *p)
 #ifndef HAVE_DEV_DLPI
 	char dname2[100];
 #endif
-	int err = PCAP_ERROR;
+	int status = PCAP_ERROR;
 
 	p->fd = -1;	/* indicate that it hasn't been opened yet */
 	p->send_fd = -1;
@@ -363,7 +363,7 @@ pcap_activate_dlpi(pcap_t *p)
 	 */
 	cp = split_dname(dname, &ppa, p->errbuf);
 	if (cp == NULL) {
-		err = PCAP_ERROR_NO_SUCH_DEVICE;
+		status = PCAP_ERROR_NO_SUCH_DEVICE;
 		goto bad;
 	}
 	*cp = '\0';
@@ -382,7 +382,7 @@ pcap_activate_dlpi(pcap_t *p)
 	cp = "/dev/dlpi";
 	if ((p->fd = open(cp, O_RDWR)) < 0) {
 		if (errno == EPERM || errno == EACCES)
-			err = PCAP_ERROR_PERM_DENIED;
+			status = PCAP_ERROR_PERM_DENIED;
 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 		    "%s: %s", cp, pcap_strerror(errno));
 		goto bad;
@@ -409,7 +409,7 @@ pcap_activate_dlpi(pcap_t *p)
 	 */
 	ppa = get_dlpi_ppa(p->fd, dname, ppa, p->errbuf);
 	if (ppa < 0) {
-		err = ppa;
+		status = ppa;
 		goto bad;
 	}
 #else
@@ -431,7 +431,7 @@ pcap_activate_dlpi(pcap_t *p)
 	 */
 	cp = split_dname(dname, &ppa, p->errbuf);
 	if (cp == NULL) {
-		err = PCAP_ERROR_NO_SUCH_DEVICE;
+		status = PCAP_ERROR_NO_SUCH_DEVICE;
 		goto bad;
 	}
 
@@ -453,7 +453,7 @@ pcap_activate_dlpi(pcap_t *p)
 		/* Try again with unit number */
 		if ((p->fd = open(dname2, O_RDWR)) < 0) {
 			if (errno == ENOENT) {
-				err = PCAP_ERROR_NO_SUCH_DEVICE;
+				status = PCAP_ERROR_NO_SUCH_DEVICE;
 
 				/*
 				 * We provide an error message even
@@ -480,7 +480,7 @@ pcap_activate_dlpi(pcap_t *p)
 				    "%s: No DLPI device found", p->opt.source);
 			} else {
 				if (errno == EACCES)
-					err = PCAP_ERROR_PERM_DENIED;
+					status = PCAP_ERROR_PERM_DENIED;
 				snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s: %s",
 				    dname2, pcap_strerror(errno));
 			}
@@ -503,8 +503,8 @@ pcap_activate_dlpi(pcap_t *p)
 		isatm = 1;
 #endif
 	if (infop->dl_provider_style == DL_STYLE2) {
-		err = dl_doattach(p->fd, ppa, p->errbuf);
-		if (err < 0)
+		status = dl_doattach(p->fd, ppa, p->errbuf);
+		if (status < 0)
 			goto bad;
 #ifdef DL_HP_RAWDLS
 		if (p->send_fd >= 0) {
@@ -519,7 +519,7 @@ pcap_activate_dlpi(pcap_t *p)
 		 * This device exists, but we don't support monitor mode
 		 * any platforms that support DLPI.
 		 */
-		err = PCAP_ERROR_RFMON_NOTSUP;
+		status = PCAP_ERROR_RFMON_NOTSUP;
 		goto bad;
 	}
 
@@ -615,9 +615,7 @@ pcap_activate_dlpi(pcap_t *p)
 #if !defined(__hpux) && !defined(sinix)
 		if (dlpromisconreq(p->fd, DL_PROMISC_MULTI, p->errbuf) < 0 ||
 		    dlokack(p->fd, "promisc_multi", (char *)buf, p->errbuf) < 0)
-			fprintf(stderr,
-			    "WARNING: DL_PROMISC_MULTI failed (%s)\n",
-			    p->errbuf);
+			status = PCAP_WARNING;
 #endif
 	}
 	/*
@@ -637,8 +635,7 @@ pcap_activate_dlpi(pcap_t *p)
 	    dlokack(p->fd, "promisc_sap", (char *)buf, p->errbuf) < 0)) {
 		/* Not fatal if promisc since the DL_PROMISC_PHYS worked */
 		if (p->opt.promisc)
-			fprintf(stderr,
-			    "WARNING: DL_PROMISC_SAP failed (%s)\n", p->errbuf);
+			status = PCAP_WARNING;
 		else
 			goto bad;
 	}
@@ -706,10 +703,11 @@ pcap_activate_dlpi(pcap_t *p)
 	release = get_release(&osmajor, &osminor, &osmicro);
 	if (osmajor == 5 && (osminor <= 2 || (osminor == 3 && osmicro < 2)) &&
 	    getenv("BUFMOD_FIXED") == NULL) {
-		fprintf(stderr,
-		"WARNING: bufmod is broken in SunOS %s; ignoring snaplen.\n",
+		snprintf(p->errbuf,
+		"WARNING: bufmod is broken in SunOS %s; ignoring snaplen.",
 		    release);
 		ss = 0;
+		status = PCAP_WARNING;
 	}
 #endif
 
@@ -732,6 +730,10 @@ pcap_activate_dlpi(pcap_t *p)
 	if (pcap_alloc_databuf(p) != 0)
 		goto bad;
 
+	/* Success - but perhaps with a warning */
+	if (status < 0)
+		status = 0;
+
 	/*
 	 * "p->fd" is an FD for a STREAMS device, so "select()" and
 	 * "poll()" should work on it.
@@ -748,13 +750,13 @@ pcap_activate_dlpi(pcap_t *p)
 	p->stats_op = pcap_stats_dlpi;
 	p->close_op = pcap_close_dlpi;
 
-	return (0);
+	return (status);
 bad:
 	if (p->fd >= 0)
 		close(p->fd);
 	if (p->send_fd >= 0)
 		close(p->send_fd);
-	return (err);
+	return (status);
 }
 
 /*

pcap-linux.c

@@ -34,7 +34,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/libpcap/pcap-linux.c,v 1.144 2008-04-09 19:58:02 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/pcap-linux.c,v 1.145 2008-04-09 21:26:12 guy Exp $ (LBL)";
 #endif
 
 /*
@@ -486,7 +486,7 @@ static int
 pcap_activate_linux(pcap_t *handle)
 {
 	const char	*device;
-	int		err;
+	int		status = 0;
 	int		activate_ok = 0;
 
 	device = handle->opt.source;
@@ -513,6 +513,7 @@ pcap_activate_linux(pcap_t *handle)
 			/* Just a warning. */
 			snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 			    "Promiscuous mode not supported on the \"any\" device");
+			status = PCAP_WARNING_PROMISC_NOTSUP;
 		}
 
 	} else
@@ -534,7 +535,7 @@ pcap_activate_linux(pcap_t *handle)
 	 * trying both methods with the newer method preferred.
 	 */
 
-	if ((err = activate_new(handle)) == 1) {
+	if ((status = activate_new(handle)) == 1) {
 		activate_ok = 1;
 		/*
 		 * Try to use memory-mapped access.
@@ -542,9 +543,9 @@ pcap_activate_linux(pcap_t *handle)
 		if (activate_mmap(handle) == 1)
 			return 0;	/* we succeeded; nothing more to do */
 	}
-	else if (err == 0) {
+	else if (status == 0) {
 		/* Non-fatal error; try old way */
-		if ((err = activate_old(handle)) == 1)
+		if ((status = activate_old(handle)) == 1)
 			activate_ok = 1;
 	}
 	if (!activate_ok) {
@@ -565,7 +566,7 @@ pcap_activate_linux(pcap_t *handle)
 		    sizeof(handle->opt.buffer_size)) == -1) {
 			snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 				 "SO_RCVBUF: %s", pcap_strerror(errno));
-			err = PCAP_ERROR;
+			status = PCAP_ERROR;
 			goto fail;
 		}
 	}
@@ -576,7 +577,7 @@ pcap_activate_linux(pcap_t *handle)
 	if (!handle->buffer) {
 		snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 			 "malloc: %s", pcap_strerror(errno));
-		err = PCAP_ERROR;
+		status = PCAP_ERROR;
 		goto fail;
 	}
 
@@ -586,7 +587,7 @@ pcap_activate_linux(pcap_t *handle)
 	 */
 	handle->selectable_fd = handle->fd;
 
-	return 0;
+	return status;
 
 fail:
 	close(handle->fd);
@@ -594,7 +595,7 @@ fail:
 		free(handle->md.device);
 		handle->md.device = NULL;
 	}
-	return err;
+	return status;
 }
 
 /*

pcap.c

@@ -33,7 +33,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/libpcap/pcap.c,v 1.117 2008-04-09 19:58:02 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/pcap.c,v 1.118 2008-04-09 21:26:12 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -211,12 +211,12 @@ pcap_set_buffer_size(pcap_t *p, int buffer_size)
 int
 pcap_activate(pcap_t *p)
 {
-	int err;
+	int status;
 
-	err = p->activate_op(p);
-	if (err == 0)
+	status = p->activate_op(p);
+	if (status >= 0)
 		p->activated = 1;
-	return (err);
+	return (status);
 }
 
 pcap_t *

pcap/pcap.h

@@ -31,7 +31,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * @(#) $Header: /tcpdump/master/libpcap/pcap/pcap.h,v 1.8 2008-04-09 19:58:02 guy Exp $ (LBL)
+ * @(#) $Header: /tcpdump/master/libpcap/pcap/pcap.h,v 1.9 2008-04-09 21:26:12 guy Exp $ (LBL)
  */
 
 #ifndef lib_pcap_pcap_h
@@ -226,7 +226,12 @@ struct pcap_addr {
 typedef void (*pcap_handler)(u_char *, const struct pcap_pkthdr *,
 			     const u_char *);
 
-/* list of known error codes for pcap API */
+/*
+ * Error codes for the pcap API.
+ * These will all be negative, so you can check for the success or
+ * failure of a call that returns these codes by checking for a
+ * negative value.
+ */
 #define PCAP_ERROR			-1	/* generic error code */
 #define PCAP_ERROR_BREAK		-2	/* loop terminated by pcap_breakloop */
 #define PCAP_ERROR_NOT_ACTIVATED	-3	/* the capture needs to be activated */
@@ -236,6 +241,14 @@ typedef void (*pcap_handler)(u_char *, const struct pcap_pkthdr *,
 #define PCAP_ERROR_NOT_RFMON		-7	/* operation supported only in monitor mode */
 #define PCAP_ERROR_PERM_DENIED		-8	/* no permission to open the device */
 
+/*
+ * Warning codes for the pcap API.
+ * These will all be positive and non-zero, so they won't look like
+ * errors.
+ */
+#define PCAP_WARNING			1	/* generic warning code */
+#define PCAP_WARNING_PROMISC_NOTSUP	2	/* this device doesn't support promiscuous mode */
+
 char	*pcap_lookupdev(char *);
 int	pcap_lookupnet(const char *, bpf_u_int32 *, bpf_u_int32 *, char *);
 

pcap_activate.3pcap

@@ -1,4 +1,4 @@
-.\" @(#) $Header: /tcpdump/master/libpcap/pcap_activate.3pcap,v 1.3 2008-04-09 20:20:17 guy Exp $
+.\" @(#) $Header: /tcpdump/master/libpcap/pcap_activate.3pcap,v 1.4 2008-04-09 21:26:12 guy Exp $
 .\"
 .\" Copyright (c) 1994, 1996, 1997
 .\"	The Regents of the University of California.  All rights reserved.
@@ -39,7 +39,12 @@ at packets on the network, with the options that were set on the handle
 being in effect.
 .SH RETURN VALUE
 .B pcap_activate()
-returns 0 on success,
+returns 0 on success without warnings,
+.B PCAP_WARNING_PROMISC_NOTSUP
+on success on a device that doesn't support promiscuous mode if
+promiscuous mode was requested,
+.B PCAP_WARNING
+on success with any other warning,
 .B PCAP_ERROR_ACTIVATED
 if the handle has already been activated,
 .B PCAP_ERROR_NO_SUCH_DEVICE
@@ -53,6 +58,8 @@ monitor mode, and
 .B PCAP_ERROR
 if an error occurred.
 If
+.B PCAP_WARNING
+or
 .B PCAP_ERROR
 is returned,
 .B pcap_geterr()
@@ -60,9 +67,11 @@ or
 .B pcap_perror()
 may be called with
 .I p
-as an argument to fetch or display the error text.
+as an argument to fetch or display a message describing the warning or
+error.
 If
-.B PCAP_ERROR_NO_SUCH_DEVICE
+.BR PCAP_WARNING_PROMISC_NOTSUP ,
+.BR PCAP_ERROR_NO_SUCH_DEVICE ,
 or
 .B PCAP_ERROR_PERM_DENIED
 is returned,
@@ -71,8 +80,8 @@ or
 .B pcap_perror()
 may be called with
 .I p
-as an argument to fetch or display an error message giving additional
-details about the error that might be useful for debugging the error if
-it's unexpected.
+as an argument to fetch or display an message giving additional details
+about the problem that might be useful for debugging the problem if it's
+unexpected.
 .SH SEE ALSO
 pcap(3PCAP)