diff options
| -rw-r--r-- | pcap.3 | 11 |
1 files changed, 10 insertions, 1 deletions
@@ -1,4 +1,4 @@ -.\" @(#) $Header: /tcpdump/master/libpcap/Attic/pcap.3,v 1.39 2002-10-18 08:46:15 guy Exp $ +.\" @(#) $Header: /tcpdump/master/libpcap/Attic/pcap.3,v 1.40 2002-12-17 07:32:55 guy Exp $ .\" .\" Copyright (c) 1994, 1996, 1997 .\" The Regents of the University of California. All rights reserved. @@ -488,6 +488,15 @@ of 1) and returns a pointer to the data in that packet. (The .I pcap_pkthdr struct for that packet is not supplied.) +.B NULL +is returned if an error occured, or if no packets were read from a live +capture (if, for example, they were discarded because they didn't pass +the packet filter, or if, on platforms that support a read timeout that +starts before any packets arrive, the timeout expires before any packets +arrive, or if the file descriptor for the capture device is in +non-blocking mode and no packets were available to be read), or if no +more packets are available in a ``savefile.'' Unfortunately, there is +no way to determine whether an error occured or not. .PP .B pcap_dump() outputs a packet to the ``savefile'' opened with |