These bindings are in opengl/util and not in opengl.
These procedures can be used to load shaders written in GLSL (the GL Shading Language). Note that these, too, should only be called when an OpenGL context is active!
file:(or/cpath-string?input-port?)shader-type:exact-nonnegative-integer?
The parameter shader-type is typically either GL_VERTEX_SHADER or GL_FRAGMENT_SHADER, although modern OpenGL versions define many more shader types. The returned shader object is already compiled and can be passed directly into create-program.
This procedure takes shaders as created by load-shader and links them together into a single program. The resulting program is already linked and can be passed directly into glUseProgram.