From: dmitri <100334....@compuserve.com>
Subject: ???---Running SCO bin's - is it emulating ---???
Date: 1995/10/26
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Hi,

Friend of mine has some apps for SCO And I know that it's possible to run them
in  Linux using iBSC ( or whatever) libs. So does it mean that with these libs
I will be emulating SCO and loos dramaticly in speed or they will be running
OK.

Thank you,



----
Dmitri
100334....@compuserve.com

From: Mike Jagdis <ja...@purplet.demon.co.uk>
Subject: ???---Running SCO bin's - is it emulating ---???
Date: 1995/10/27
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* In message <46oo28...@docder.demon.co.uk>, dmitri said:

dd> Friend of mine has some apps for SCO And I know that it's
dd> possible to run them
dd> in  Linux using iBSC ( or whatever) libs. So does it mean
dd> that with these libs
dd> I will be emulating SCO and loos dramaticly in speed or they
dd> will be running OK.

The iBCS "emulator" is a loadable kernel module that allows the kernel to 
handle SCO system calls. It's an emulator only in so far as some parameters 
and returns from system calls need to be converted between SCO and Linux 
values and some extra magic needs to be invoked for some things. 90% of the 
time your applications will be running their own code at normal speed.

  The iBCS emulator does add a slight overhead to system calls - as compared 
to the native Linux system calls. This overhead is not likely to be 
significant for real applications. Comparing Linux+iBCS to a real SCO system 
I tend to find that system call overhead favours Linux - but, again, you 
aren't going to see any significant difference due simply to that.

  Many have reported that applications ran as fast or even faster than on 
SCO (probably mostly due to Linux' use of free memory for caching). I can't 
remember any reports of slow downs but that doesn't mean to say I can't 
envisage situations where it _could_ happen.

                                Mike