---
name: "Xfontcache"
section: "3"
platform: "linux"
package: "libxfontcache-dev"
version: "1.0.4-1"
release: "Debian 5.0 (Lenny)"
platforms: ["linux"]
url: "https://new.carta.tech/Xfontcache"
---

# Xfontcache(3)

X-TrueType font cache extension client library

## NAME

Xfontcache - X-TrueType font cache extension client library

## SYNOPSIS

**#include \<X11/extensions/FontCache.h\>**

```
typedef struct {
	long	himark;
	long	lowmark;
	long	balance;
} FontCacheSettings, *FontCacheSettingsPtr;
struct cacheinfo {
	long	hits;
	long	misshits;
	long	purged;
	long	usage;
};
typedef struct {
	long	purge_runs;
	long	purge_stat;
	long	balance;
	struct cacheinfo	f;
	struct cacheinfo	v;
} FontCacheStatistics, *FontCacheStatisticsPtr;
```

Bool FontCacheQueryExtension(Display \**dpy*,  int \**event\_basep*, int \**error\_basep*);

Status FontCacheQueryVersion(Display \**dpy*, int \**major\_versionp*, int \**minor\_versionp*);

Status FontCacheGetCacheSettings(Display \**dpy*, FontCacheSettings \**cache info*);

Status FontCacheChangeCacheSettings(Display \**dpy*, FontCacheSettings \**cache info*);

Status FontCacheGetCacheStatistics(Display \**dpy*, FontCacheStatistics \**cache statistics info*);

## DESCRIPTION

**FontCache** is an extension that is used by X-TrueType to cache informations about fonts.

**FontCacheQueryExtension** returns **True** if the  *FontCache* extension is available on the given display. A client must call  **FontCacheQueryExtension** before calling any other Xfontcache function in order to negotiate a compatible protocol version; otherwise the client will get undefined behavior (Xfontcache may or may not work).

**FontCacheQueryVersion** returns **True** if the request succeeded; the values of the major and minor protocol versions supported by the server are returned in  *major\_versionp* and  *minor\_versionp .*

**FontCacheGetCacheSettings** should be documented here.  Returns  **True** on success or  **False** on failure.

**FontCacheChangeCacheSettings** should be documented here. Returns  **True** on success or  **False** on failure.

**FontCacheGetCacheStatistics** should be documented here. Returns  **True** on success or  **False** on failure.

## ERRORS

**FontCacheChangeCacheSettings** will return  *BadValue* if passed an illegal parameters for lowmark, himark or balance fields.

## SEE ALSO

[X(7)](/X/7.md)

## AUTHOR

Akio Morita, X-TrueType team, Nozomi Ytow.

## STABILITY

This API is considered as experimental. The Xfontcache library major revision may be incremented whenever incompatible changes are done to the API without notice. Use with care.