| pcap_next_ex.3pcap (214518) | pcap_next_ex.3pcap (235426) |
|---|---|
| 1.\" @(#) $Header: /tcpdump/master/libpcap/pcap_next_ex.3pcap,v 1.3 2008-04-06 02:53:22 guy Exp $ 2.\" 3.\" Copyright (c) 1994, 1996, 1997 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that: (1) source code distributions 8.\" retain the above copyright notice and this paragraph in its entirety, (2) --- 31 unchanged lines hidden (view full) --- 40reads the next packet and returns a success/failure indication. 41If the packet was read without problems, the pointer pointed to by the 42.I pkt_header 43argument is set to point to the 44.I pcap_pkthdr 45struct for the packet, and the 46pointer pointed to by the 47.I pkt_data | 1.\" @(#) $Header: /tcpdump/master/libpcap/pcap_next_ex.3pcap,v 1.3 2008-04-06 02:53:22 guy Exp $ 2.\" 3.\" Copyright (c) 1994, 1996, 1997 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that: (1) source code distributions 8.\" retain the above copyright notice and this paragraph in its entirety, (2) --- 31 unchanged lines hidden (view full) --- 40reads the next packet and returns a success/failure indication. 41If the packet was read without problems, the pointer pointed to by the 42.I pkt_header 43argument is set to point to the 44.I pcap_pkthdr 45struct for the packet, and the 46pointer pointed to by the 47.I pkt_data |
| 48argument is set to point to the data in the packet. | 48argument is set to point to the data in the packet. The 49.I struct pcap_pkthdr 50and the packet data are not to be freed by the caller, and are not 51guaranteed to be valid after the next call to 52.BR pcap_next_ex() , 53.BR pcap_next() , 54.BR pcap_loop() , 55or 56.BR pcap_dispatch() ; 57if the code needs them to remain valid, it must make a copy of them. |
| 49.PP 50.B pcap_next() 51reads the next packet (by calling 52.B pcap_dispatch() 53with a 54.I cnt 55of 1) and returns a 56.I u_char | 58.PP 59.B pcap_next() 60reads the next packet (by calling 61.B pcap_dispatch() 62with a 63.I cnt 64of 1) and returns a 65.I u_char |
| 57pointer to the data in that packet. | 66pointer to the data in that packet. The 67packet data is not to be freed by the caller, and is not 68guaranteed to be valid after the next call to 69.BR pcap_next_ex() , 70.BR pcap_next() , 71.BR pcap_loop() , 72or 73.BR pcap_dispatch() ; 74if the code needs it to remain valid, it must make a copy of it. |
| 58The 59.I pcap_pkthdr 60structure pointed to by 61.I h 62is filled in with the appropriate values for the packet. 63.SH RETURN VALUE 64.B pcap_next_ex() 65returns 1 if the packet was read without problems, 0 --- 7 unchanged lines hidden (view full) --- 73.B pcap_perror() 74may be called with 75.I p 76as an argument to fetch or display the error text. 77.PP 78.B pcap_next() 79returns a pointer to the packet data on success, and returns 80.B NULL | 75The 76.I pcap_pkthdr 77structure pointed to by 78.I h 79is filled in with the appropriate values for the packet. 80.SH RETURN VALUE 81.B pcap_next_ex() 82returns 1 if the packet was read without problems, 0 --- 7 unchanged lines hidden (view full) --- 90.B pcap_perror() 91may be called with 92.I p 93as an argument to fetch or display the error text. 94.PP 95.B pcap_next() 96returns a pointer to the packet data on success, and returns 97.B NULL |
| 81if an error occured, or if no packets were read from a live | 98if an error occurred, or if no packets were read from a live |
| 82capture (if, for example, they were discarded because they didn't pass 83the packet filter, or if, on platforms that support a read timeout that 84starts before any packets arrive, the timeout expires before any packets 85arrive, or if the file descriptor for the capture device is in 86non-blocking mode and no packets were available to be read), or if no 87more packets are available in a ``savefile.'' Unfortunately, there is | 99capture (if, for example, they were discarded because they didn't pass 100the packet filter, or if, on platforms that support a read timeout that 101starts before any packets arrive, the timeout expires before any packets 102arrive, or if the file descriptor for the capture device is in 103non-blocking mode and no packets were available to be read), or if no 104more packets are available in a ``savefile.'' Unfortunately, there is |
| 88no way to determine whether an error occured or not. | 105no way to determine whether an error occurred or not. |
| 89.SH SEE ALSO 90pcap(3PCAP), pcap_geterr(3PCAP), pcap_dispatch(3PCAP) | 106.SH SEE ALSO 107pcap(3PCAP), pcap_geterr(3PCAP), pcap_dispatch(3PCAP) |