glGetActiveUniform Interface to
OpenGL function glGetActiveUniform
usage: [ length, size, type, name ] = glGetActiveUniform( program, index, bufSize )
C function: void glGetActiveUniform(GLuint program, GLuint index, GLsizei bufSize, GLsizei* length, GLsizei* size, GLenum* type, GLchar* name)
Psychtoolbox/PsychOpenGL/MOGL/wrap/_glGetActiveUniform.m