glXQueryContextInfoEXT

query context information

C Specification

`int glXQueryContextInfoEXT(`	Display *	`dpy`,
	GLXContext	`ctx`,
	int	`attribute`,
	int *	`value)`;

Parameters

dpy: Specifies the connection to the X server.
ctx: Specifies a GLX rendering context.
attribute: Specifies that a context parameter should be retrieved. Must be one of GLX_SHARED_CONTEXT_EXT, GLX_VISUAL_ID_EXT, or GLX_SCREEN_EXT.
value: Contains the return value for attribute.

Description

glXQueryContextInfoEXT sets value to the value of attribute with respect to ctx. glXQueryContextInfoEXT returns an error code if it fails for any reason. Otherwise, Success is returned.

attribute may be one of the following:

GLX_SHARED_CONTEXT_EXT: Returns the XID of the share list context associated with ctx at its creation.
GLX_VISUAL_ID_EXT: Returns the XID of the GLX Visual associated with ctx.
GLX_SCREEN_EXT: Returns the screen number associated with ctx.

This call may cause a round-trip to the server.

glXQueryContextInfoEXT is part of the EXT_import_context extension, not part of the core GLX command set. If _glxextstring(EXT_import_context) is included in the string returned by glXQueryExtensionsString, when called with argument GLX_EXTENSIONS, extension EXT_import_context is supported.

Errors

GLXBadContext is generated if ctx does not refer to a valid context.

GLX_BAD_ATTRIBUTE is returned if attribute is not a valid GLX context attribute.

fred GLX_BAD_CONTEXT is returned if attribute is not a valid context.