---
name: "xcb_big_requests_enable"
section: "3"
platform: "linux"
package: "libxcb"
version: "1.17.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/xcb_big_requests_enable"
---

# xcb\_big\_requests\_enable(3)

Enable the BIG-REQUESTS extension

## NAME

xcb\_big\_requests\_enable - Enable the BIG-REQUESTS extension

## SYNOPSIS

**#include \<xcb/bigreq.h\>**

### Request function

xcb\_big\_requests\_enable\_cookie\_t **xcb\_big\_requests\_enable**(xcb\_connection\_t \**conn*,

### Reply datastructure

```

typedef struct xcb_big_requests_enable_reply_t {
    uint8_t  response_type;
    uint8_t  pad0;
    uint16_t sequence;
    uint32_t length;
    uint32_t maximum_request_length;
} xcb_big_requests_enable_reply_t;
```

### Reply function

xcb\_big\_requests\_enable\_reply\_t \***xcb\_big\_requests\_enable\_reply**(xcb\_connection\_t \**conn*, xcb\_big\_requests\_enable\_cookie\_t *cookie*, xcb\_generic\_error\_t \*\**e*);\

## REQUEST ARGUMENTS

- *conn*

  The XCB connection to X11.

## REPLY FIELDS

- *response\_type*

  The type of this reply, in this case *XCB\_BIG\_REQUESTS\_ENABLE*. This field is also present in the *xcb\_generic\_reply\_t* and can be used to tell replies apart from each other.

- *sequence*

  The sequence number of the last request processed by the X11 server.

- *length*

  The length of the reply, in words (a word is 4 bytes).

- *maximum\_request\_length*

  The maximum length of requests supported by the server, in 4-byte units.

## DESCRIPTION

This enables the BIG-REQUESTS extension, which allows for requests larger than 262140 bytes in length.  When enabled, if the 16-bit length field is zero, it is immediately followed by a 32-bit length field specifying the length of the request in 4-byte units.

## RETURN VALUE

Returns an *xcb\_big\_requests\_enable\_cookie\_t*. Errors have to be handled when calling the reply function *xcb\_big\_requests\_enable\_reply*.

If you want to handle errors in the event loop instead, use *xcb\_big\_requests\_enable\_unchecked*. See **[xcb-requests(3)](/xcb-requests/3.md)** for details.

## ERRORS

This request does never generate any errors.

## SEE ALSO

[**xcb-requests**(3)](/xcb-requests/3.md)

## AUTHOR

Generated from bigreq.xml. Contact xcb@lists.freedesktop.org for corrections and improvements.