What does cdbx do to subprocesses ?

Booker bense booker at network.ucsd.edu
Sat Sep 29 07:29:03 AEST 1990


Howdy,

	Does anyone out there know what cdbx 5.1 does to a process
before runs it? I have a program that runs fine when run with

cdbx -L 'myprogram args'
(cdbx) run

However (without recompiling),

myprogram args

by itself produces bad results. My program opens sockets and receives
requests then crunches numbers in a fortran subroutine, dumping the
results back through the socket to a workstation. Run in cdbx the
results are fine and appear about four times faster(wallclock), than
when run alone.

The results that appear in the array back at the work station have the 
first 64 results ok, the rest are trashed or the first 64 are repeated 
over and over. 

History:
 The first version of this program runs fine. I then went into the
fortran routine and got it running about 30+ mflops faster (no
Autotasking), in doing this I probably doubled the size of memory used
by the subroutine.


Suspicions:

	Cdbx is doing something to the way the program handles
memory , or doing something with signals before it forks off the
program as a subprocess. If I knew what this was I would duplicate 
this and shake my mojo over the keyboard, throw some salt over my shoulder
and continue. 

Any clues would be gratefully appreciated.


Booker C. Bense

/* benseb at grumpy.sdsc.edu */

P.S. the c part was compiled with ssc , the fortran part with cf77 -Zv
( cf77 4.0)



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