---
name: "pcap_dump_ftell"
section: "3"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd"]
url: "https://new.carta.tech/pcap_dump_ftell"
---

# pcap\_dump\_ftell(3)

get the current file offset for a savefile being written

## 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**(3)](/pcap_dump_open/3.md) **and** [**pcap\_dump**(3)](/pcap_dump/3.md). **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

**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**(3)](/pcap/3.md)