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Date: Fri, 13 Aug 2004 03:52:17 +0200
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Subject: Interrupt 0x80 handling
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Hi,
giving a look to interrupt 0x80 handling code (i386/i386/exception.s), I'=
ve
met FAKE_MCOUNT/MEXITCOUNT system. FAKE_MCOUNT in the end calls _mcount
(libkern/mcount.c) function which seems to be used for profiling purposes=

IMHO. It seems (reading comments in sys/gmon.h) that sysctl could be used=

to manage syscall profiling (kernel profiling?): Somebody can confirm tha=
t
or I've misunderstood? I would like to know another thing too: why interr=
upt
0x80 handler is implemented through a trap gate? An interrupt gate could
not be more logical?

thanks for answers,
cheers

rookie