topic Re: Coredump in kornshell but not in possix? in Operating System - HP-UX

Coredump in kornshell but not in possix?

Danny Engelbarts — Fri, 24 Nov 2000 11:12:52 GMT

Hi,

I noticed something weird in the kornshell, the attached script will generate a memory fault (SIGSEGV) when executed using /usr/bin/ksh but when the first line is changed to #!/usr/bin/sh it will run without any problems! Does anyone have a clue what's going on? (Seems like a bug to me ...)

Greetz, Danny

Re: Coredump in kornshell but not in possix?

Dave Kelly_1 — Fri, 24 Nov 2000 11:44:06 GMT

I've just run your script on my 10.20 system without a problem.

What OS do you have ? Patches ?

Can you also supply the stderr output seeing as you included set -x in the script. It would be good to see exactly where the SIGSEGV is occurring.

Re: Coredump in kornshell but not in possix?

Danny Engelbarts — Fri, 24 Nov 2000 12:18:32 GMT

Hey Dave,

Here's some more info (attachment), although i did include the set -x there is no debug output?
I ran the original on a 10.10 system, i've tried on 10.20 as well and i get the same error.

Greetz, Danny.

Re: Coredump in kornshell but not in possix?

Rainer_1 — Fri, 24 Nov 2000 12:21:45 GMT

don't know why but the problem points to the shift statement within the while getopts ... do ... done loop
Remove the shift line and add after the loop

shift $(($OPTIND -1))

then the script runs at both shells

Re: Coredump in kornshell but not in possix?

Danny Engelbarts — Fri, 24 Nov 2000 12:40:45 GMT

Yep! That's it ... still wondering why now ;o)

Thanks! Danny.

Re: Coredump in kornshell but not in possix?

Carlos Fernandez Riera — Fri, 24 Nov 2000 13:01:37 GMT

Your problem is you are making too shifts ( more than arguments).

insert echo $# $* before shift and run.

See man getopts:

thera are an example that use shift out of loop and ussing $OPTIND.

HTH

Re: Coredump in kornshell but not in possix?

Danny Engelbarts — Fri, 24 Nov 2000 13:31:40 GMT

Hmmm,

If i read the manual correctly getopts should only walk through the "legal options" i.e. all options with either a preceding - or + sign. But it seems the implementation in the kornshell walks through the other options as well?

Danny.

Re: Coredump in kornshell but not in possix?

Carlos Fernandez Riera — Fri, 24 Nov 2000 13:49:22 GMT

I understand that getopts may search over all args to find all options.

For your script perhaps you will prefer:

DiffTime -h -s time -e time

and getopt hs:e:.

See man 3c getopt too.

Re: Coredump in kornshell but not in possix?

CHRIS_ANORUO — Fri, 24 Nov 2000 15:32:56 GMT

Hi Danny,

Check with this command "swlist -l fileset|grep sh" to see if you have patch PHKL_19762 installed on your server.
The patch is a fix for debugging shared lib gets SIGSEGV problem.

Re: Coredump in kornshell but not in possix?

Bill Hassell — Sat, 25 Nov 2000 22:20:52 GMT

Just a note about debugging (tracing with set -x): the trace output will go to stderr. So to trace a shell script with all output into a file:

sh -x myscript arg1 arg2 > /var/tmp/tracefile 2>&1