pcap_dump_ftell(3PCAP) man page

pcap_dump_ftell(3PCAP) man page

Updated: 25 July 2018 • View in plain text • Return to Main Contents

NAME

pcap_dump_ftell, pcap_dump_ftell64 - get the current file offset for a savefile being written

SYNOPSIS

#include <pcap/pcap.h>

long pcap_dump_ftell(pcap_dumper_t *p);
int64_t pcap_dump_ftell64(pcap_dumper_t *p);

DESCRIPTION

pcap_dump_ftell() returns the current file position for the `savefile'', representing the number of bytes written by [**pcap\_dump\_open**](https://www.tcpdump.org/manpages/pcap_dump_open.3pcap.html)(3PCAP) and [**pcap\_dump**](https://www.tcpdump.org/manpages/pcap_dump.3pcap.html)(3PCAP).PCAP_ERRORis returned on error. If the current file position does not fit in along, it will be truncated; this can happen on 32-bit UNIX-like systems with large file support and on Windows. **pcap\_dump\_ftell64**() returns the current file position in aint64_t, so if file offsets that don't fit in alongbut that fit in aint64_tare supported, this will return the file offset without truncation.PCAP_ERROR` is returned on error.

BACKWARD COMPATIBILITY

The function pcap_dump_ftell64() became available in libpcap release 1.9.0. In previous releases, there was no mechanism to obtain a file offset that is too large to fit in a long.

SEE ALSO

pcap(3PCAP)

COLOPHON

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