---
name: "libssh2_trace_sethandler"
section: "3"
platform: "linux"
package: "libssh2"
version: "1.11.1-7"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/libssh2_trace_sethandler"
---

# libssh2\_trace\_sethandler(3)

set a trace output handler

## NAME

libssh2\_trace\_sethandler - set a trace output handler

## SYNOPSIS

```
#include <libssh2.h>
typedef void (*libssh2_trace_handler_func)(LIBSSH2_SESSION *session,
                                           void *context,
                                           const char *data,
                                           size_t length);
int
libssh2_trace_sethandler(LIBSSH2_SESSION *session,
                         void *context,
                         libssh2_trace_handler_func callback);
```

## DESCRIPTION

libssh2\_trace\_sethandler installs a trace output handler for your application. By default, when tracing has been switched on via a call to libssh2\_trace(), all output is written to stderr. By calling this method and passing a function pointer that matches the libssh2\_trace\_handler\_func prototype, libssh2 will call back as it generates trace output. This can be used to capture the trace output and put it into a log file or diagnostic window. This function has no effect unless libssh2 was built to support this option, and a typical "release build" might not.

**context** can be used to pass arbitrary user defined data back into the callback when invoked.

## AVAILABILITY

Added in libssh2 version 1.2.3