site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com Organization: Duiker Research Thread-index: Accvi2jRrPvzwRYiQ+e9QFEQJ6+czA== Hello, I’m in the process of writing a simple tool that will allow users to dynamically switch between their existing monitor profiles and other luts. I’m running into the same stumbling block that the message below mentions, namely that IOServiceOpen is failing to open the IOFramebuffer service because the window server has exclusive access to it. Are there other apis that should be used for accessing the graphic card’s gamma table? Any help you can provide would be appreciated. Regards, HP Duiker Duiker Research Referenced message can be found here: http://lists.apple.com/archives/darwin-kernel/2005/Apr/msg00074.html Text: Hi Amit, I am trying to execute the code written below. Here IOServiceOpen is giving error   -536870203 Can any one tell the reason for this error. There's documentation that describes how to interpret I/O Kit error codes. <http://developer.apple.com/documentation/DeviceDrivers/Conceptual/AccessingHardware/AH_Handling_Errors/chapter_6_section_2.html> In this case, -536870203 is 0xe00002c5, which indicates a system of I/O Kit (0x38) and, within that, the common subsystem (0).  The error value is that in <IOKit/IOReturn.h>, namely: There's documentation about this error code as well. <http://developer.apple.com/documentation/DeviceDrivers/Conceptual/AccessingHardware/AH_Handling_Errors/chapter_6_section_3.html> What is it you are trying to do? Cheers, -- J-Sun Seng Networking & Communications / Hardware Developer Technical Support Apple Computer, Inc. #1 Infinite Loop M/S: 303-2T _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... This email sent to site_archiver@lists.apple.com At 17:14 +0530 15/4/05, Amit Gupta wrote: #define kIOReturnExclusiveAccess iokit_common_err(0x2c5)// exclusive access and // device already open The Window Server has the IOFramebufferUserClient open exclusively, thus the reason for the error you are seeing.