PCAP\_DUMP\_FTELL(3PCAP) PCAP\_DUMP\_FTELL(3PCAP) # [NAME](#NAME) pcap\_dump\_ftell, pcap\_dump\_ftell64 - get the current file offset for a savefile being written # [SYNOPSIS](#SYNOPSIS) ``` #include ``` ``` long pcap_dump_ftell(pcap_dumper_t *p); int64_t pcap_dump_ftell64(pcap_dumper_t *p); ``` # [DESCRIPTION](#DESCRIPTION) **pcap\_dump\_ftell**() returns the current file position for the \`\`savefile'', representing the number of bytes written by [**pcap\_dump\_open**(3PCAP)](/man/os/libpcap/pcap_dump_open.3PCAP) and [**pcap\_dump**(3PCAP)](/man/os/libpcap/pcap_dump.3PCAP). **PCAP\_ERROR** is returned on error. If the current file position does not fit in a **long**, 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 a **int64\_t**, so if file offsets that don't fit in a **long** but that fit in a **int64\_t** are supported, this will return the file offset without truncation. **PCAP\_ERROR** is returned on error. # [BACKWARD COMPATIBILITY](#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](#SEE_ALSO) [**pcap**(3PCAP)](/man/os/libpcap/pcap.3PCAP) 25 July 2018 --- Document: pcap_dump_ftell(3pcap) from libpcap 1.11.0-r0 (Chainguard OS) Source: https://github.com/the-tcpdump-group/libpcap.git