---
name: "libssh2_channel_window_write_ex"
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_channel_window_write_ex"
---

# libssh2\_channel\_window\_write\_ex(3)

Check the status of the write window

## NAME

libssh2\_channel\_window\_write\_ex - Check the status of the write window

## SYNOPSIS

```
#include <libssh2.h>
unsigned long
libssh2_channel_window_write_ex(LIBSSH2_CHANNEL *channel,
                                unsigned long *window_size_initial)
```

## DESCRIPTION

Check the status of the write window Returns the number of bytes which may be safely written on the channel without blocking. 'window\_size\_initial' (if passed) will be populated with the size of the initial window as defined by the channel\_open request

## RETURN VALUE

Number of bytes which may be safely written on the channel without blocking.

## ERRORS

## SEE ALSO

**[libssh2\_channel\_window\_read\_ex(3)](/libssh2_channel_window_read_ex/3.md),** **[libssh2\_channel\_receive\_window\_adjust(3)](/libssh2_channel_receive_window_adjust/3.md)**