Re: [PATCH] test-lib.sh: work around ksh's trap shortcomings

From: Brandon Casey <casey@nrlssc.navy.mil>
Date: Aug 20, 2008, 00:19 UTC
Message-ID: <nEEUmh6BVMDYtwf1vENCYuaLiFUWKW_dbgPP__ECl3s@cipher.nrlssc.navy.mil>
In-Reply-To: <cqiOMMbzSSjqZoLDEa5uscl2d0D71PrGu2TpSOULLuV5nTVnEEWCzQ@cipher.nrlssc.navy.mil>

Brandon Casey wrote:

Show 7 quoted lines

> Junio C Hamano wrote:
>> Your alias test_done that calls function test_done look ugly and confusing
>> beyond words.  Perhaps test_done() can instead set a global variable and
>> die() can notice it instead, like this?  I haven't bothered to change the
>> other "trap - exit" but I think you got the idea...
> 
> Yes that works and is much clearer. Tested on solaris and irix.

I spoke too soon. Failing tests do not terminate the testing.

ksh does not place the exit status of the shell in $? or provide it as an argument to the trap function. Possibly the status of the 'exit' command is provided instead?

$ cat test.sh #!/bin/sh

die () {
    status=$?
    echo >&2 "die status: $status"
    exit $status
}

trap 'die' 0

echo "I am dying" exit 1

###### END TEST SCRIPT ######

linux $ /bin/sh test.sh I am dying die status: 1 linux $ echo $? 1

linux $ /usr/bin/ksh test.sh I am dying die status: 1 linux $ echo $? 1

IRIX $ /bin/ksh test.sh I am dying die status: 0 IRIX $ echo $? 0

SunOS $ /usr/xpg4/bin/sh test.sh I am dying die status: 0 SunOS $ echo $? 0

Ah, no, it looks like the status of the command executed immediately before exit is what the trap has access to in $?. Adding a call to false before exit in the above script causes the korn scripts to exit with status 1 on IRIX and SunOS.

#!/bin/sh

die () {
    status=$?
    echo >&2 "die status: $status"
    exit $status
}

trap 'die' 0

echo "I am dying" false exit 1

-brandon