glAreTexturesResident	- determine if textures	are loaded in
	  texture memory

	  GLboolean glAreTexturesResident( GLsizei n,
					   const GLuint	*textures,
					   GLboolean *residences )

	  n	      Specifies	the number of textures to be queried.

	  textures    Specifies	an array containing the	names of the
		      textures to be queried.

	  residences  Specifies	an array in which the texture
		      residence	status is returned.  The residence
		      status of	a texture named	by an element of
		      textures is returned in the corresponding
		      element of residences.

	  GL establishes a ``working set'' of textures that are
	  resident in texture memory.  These textures can be bound to
	  a texture target much	more efficiently than textures that
	  are not resident.

	  glAreTexturesResident	queries	the texture residence status
	  of the n textures named by the elements of textures.	If all
	  the named textures are resident, glAreTexturesResident
	  returns GL_TRUE, and the contents of residences are
	  undisturbed.	If not all the named textures are resident,
	  glAreTexturesResident	returns	GL_FALSE, and detailed status
	  is returned in the n elements	of residences.	If an element
	  of residences	is GL_TRUE, then the texture named by the
	  corresponding	element	of textures is resident.

	  The residence	status of a single bound texture may also be
	  queried by calling glGetTexParameter with the	target
	  argument set to the target to	which the texture is bound,
	  and the p_name argument set to GL_TEXTURE_RESIDENT.  This is
	  the only way that the	residence status of a default texture
	  can be queried.

	  glAreTexturesResident	is available only if the GL version is
	  1.1 or greater.

	  glAreTexturesResident	returns	the residency status of	the
	  textures at the time of invocation. It does not guarantee
	  that the textures will remain	resident at any	other time.

	  If textures reside in	virtual	memory (there is no texture
	  memory), they	are considered always resident.

	  Some implementations may not load a texture until the	first
	  use of that texture.

	  GL_INVALID_VALUE is generated	if n is	negative.

	  GL_INVALID_VALUE is generated	if any element in textures is
	  0 or does not	name a texture.	In that	case, the function
	  returns GL_FALSE and the contents of residences is

	  GL_INVALID_OPERATION is generated if glAreTexturesResident
	  is executed between the execution of glBegin and the
	  corresponding	execution of glEnd.

	  glGetTexParameter with parameter name	GL_TEXTURE_RESIDENT
	  retrieves the	residence status of a currently	bound texture.

	  glBindTexture, glGetTexParameter, glPrioritizeTextures,
	  glTexImage1D,	glTexImage2D, glTexParameter