tracing of system calls on Linux

[Partha Saha]

Hi,

I assume that strace works on Linux by using the
/proc filesystem.  If started by a command line argument
such as "-e write" where I indicate interest in only
the write system calls, I am wondering whether traps
are generated from _all_ system calls and then logging
done after filtering over whichever system calls I have expressed
interest in, or whether traps are generated only from
those system calls I have indicated after the "-e" option.

The second method will be obviously more efficient but I
am not sure whether the /proc filesystem allows it.

Thanks,

Partha Saha