PDF slides for Chapter 12: System Calls have been prepared and uploaded to http://seyfarth.tv/asm for downloading.
Chapter 12 is about system calls. It describes how both 32 bit and 64 bit system calls are implemented on Linux. Interestingly the numbers used for system calls for 32 bit calls and 64 bit calls bear no obvious relation.
Using these numbers for system calls is fairly pointless since there are C wrapper functions for each system call which have easy to remember names and a little added capability. The time taken for a system call is far greater than the time taken up in using the wrapper functions, so there is little value in using system calls directly. Furthermore there is probably no reason not to write nearly all system call using code in C or C++ anyway.
12 of 19 chapter complete!
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