---
name: "al_ustr_insert"
section: "3"
platform: "linux"
package: "allegro"
version: "5.2.11.3-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/al_ustr_insert"
---

# al\_ustr\_insert(3)

Allegro 5 API

## NAME

al\_ustr\_insert - Allegro 5 API

## SYNOPSIS

-

  ```
  #include <allegro5/allegro.h>
  bool al_ustr_insert(ALLEGRO_USTR *us1, int pos, const ALLEGRO_USTR *us2)
  ```

## DESCRIPTION

Insert `us2` into `us1` beginning at byte offset `pos`. `pos` cannot be less than 0. If `pos` is past the end of `us1` then the space between the end of the string and `pos` will be padded with NUL (`'\0'`) bytes.

If required, use [al\_ustr\_offset(3)](/al_ustr_offset/3.md) to find the byte offset for a given code point index.

Returns true on success, false on error.

## SEE ALSO

[al\_ustr\_insert\_cstr(3)](/al_ustr_insert_cstr/3.md), [al\_ustr\_insert\_chr(3)](/al_ustr_insert_chr/3.md), [al\_ustr\_append(3)](/al_ustr_append/3.md), [al\_ustr\_offset(3)](/al_ustr_offset/3.md)