---
name: "SDL_islower"
section: "3"
platform: "linux"
package: "libsdl3-doc"
version: "3.2.10+ds-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/SDL_islower"
---

# SDL\_islower(3)

Report if a character is lower case.

## NAME

SDL\_islower - Report if a character is lower case.

## HEADER FILE

Defined in SDL3/SDL\_stdinc.h

## SYNOPSIS

```
#include "SDL3/SDL.h"
```

**int SDL\_islower(int x);**

## DESCRIPTION

**WARNING** : Regardless of system locale, this will only treat ASCII values

## FUNCTION PARAMETERS

- *x*

  character value to check.

## RETURN VALUE

Returns non-zero if x falls within the character class, zero otherwise.

## THREAD SAFETY

It is safe to call this function from any thread.

## AVAILABILITY

This function is available since SDL 3.2.0.