OpenGL C bindings library: libGL.a
GLenum glGetError( void )
The glGetError subroutine returns the value of the error flag. Each detectable error is assigned a numeric code and symbolic name. When an error occurs, the error flag is set to the appropriate error code value. No other errors are recorded until glGetError is called, the error code is returned, and the flag is reset to GL_NO_ERROR. If a call to glGetError returns GL_NO_ERROR, there has been no detectable error since the last call to glGetError, or since the GL was initialized.
To allow for distributed implementations, there may be several error flags. If any single error flag has recorded an error, the value of that flag is returned, and that flag is reset to GL_NO_ERROR when glGetError is called. If more than one flag has recorded an error, glGetError returns and clears an arbitrary error flag value. Therefore, glGetError should always be called in a loop, until it returns GL_NO_ERROR, if all error flags are to be reset.
Initially, all error flags are set to GL_NO_ERROR.
The currently defined errors are:
When an error flag is set, results of a GL operation are undefined only if GL_OUT_OF_MEMORY has occurred. In all other cases, the command generating the error is ignored and has no effect on the GL state or frame buffer contents.
GL_INVALID_OPERATION | The glGetError subroutine is called between a call to glBegin and the corresponding call to glEnd. |
/usr/include/GL/gl.h | Contains C language constants, variable type definitions, and ANSI function prototypes fo OpenGL. |
The glBegin or glEnd subroutine.