PFNGLGETACTIVESUBROUTINENAMEPROC

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C)
alias PFNGLGETACTIVESUBROUTINENAMEPROC = void function(GLuint program, GLenum shadertype, GLuint index, GLsizei bufsize, GLsizei* length, GLchar* name)

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