pcap_dump_ftell.3pcap

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.TH PCAP_DUMP_FTELL 3PCAP "25 July 2018"
.SH NAME
pcap_dump_ftell, pcap_dump_ftell64 \- get the current file offset for a savefile being written
.SH SYNOPSIS
.nf
.ft B
#include <pcap/pcap.h>
.ft
.LP
.ft B
long pcap_dump_ftell(pcap_dumper_t *p);
.ft B
int64_t pcap_dump_ftell64(pcap_dumper_t *p);
.ft
.fi
.SH DESCRIPTION
.BR pcap_dump_ftell ()
returns the current file position for the ``savefile'', representing the
number of bytes written by
.BR pcap_dump_open (3PCAP)
and
.BR pcap_dump (3PCAP).
.B PCAP_ERROR
is returned on error. If the current file position does not fit in a
.BR long ,
it will be truncated; this can happen on 32-bit UNIX-like systems with
large file support and on Windows.
.BR pcap_dump_ftell64 ()
returns the current file position in a
.BR int64_t ,
so if file offsets that don't fit in a
.B long
but that fit in a
.B int64_t
are supported, this will return the file offset without truncation.
.B PCAP_ERROR
is returned on error.
.SH BACKWARD COMPATIBILITY
The function
.BR 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
.BR long .
.SH SEE ALSO
.BR pcap (3PCAP)