glGetActiveUniformName

glGetActiveUniformName: man3/glGetActiveUniformName.xml

glGetActiveUniformName returns the name of the active uniform at uniformIndex within program. If uniformName is not null, up to bufSize characters (including a nul-terminator) will be written into the array whose address is specified by uniformName. If length is not null, the number of characters that were (or would have been) written into uniformName (not including the nul-terminator) will be placed in the variable whose address is specified in length. If length is null, no length is returned. The length of the longest uniform name in program is given by the value of GL_ACTIVE_UNIFORM_MAX_LENGTH, which can be queried with glGetProgram. If glGetActiveUniformName is not successful, nothing is written to length or uniformName. program must be the name of a program for which the command glLinkProgram has been issued in the past. It is not necessary for program to have been linked successfully. The link could have failed because the number of active uniforms exceeded the limit. uniformIndex must be an active uniform index of the program program, in the range zero to GL_ACTIVE_UNIFORMS - 1. The value of GL_ACTIVE_UNIFORMS can be queried with glGetProgram.