Re: feedback from a unix command run from CL

On 18-Jun-2014 14:50 -0500, Scott Klement wrote:

On 6/18/2014 2:39 PM, Mike Cunningham wrote:

Is there a way to detect the results of a unix shell command run
from a CLLE program?

I want to run the cmp qshell command from CL against two IFS files.
Cmp returns an Exit Status:
0 when the files are identical
1 when the files are different
>1 when an error occurred

I want to take additional action in the CL if the exit status is 1

When the STRQSH command is finished, it should send you a QSH0005
completion message containing the exit status.

You should be able to receive that message... the exit status should
be a binary value in the first 4 bytes of the msgdta.

The cmp utility seems to me, best utilized with the Environment Variable that forces the QSH to end with an Escape Message instead of the completion message when the request /fails/; other than a status of zero, the request is considered to have failed. That allows the condition of no mismatches to fall through to the next CL request, and either of an error or a mismatch to be caught in the EXEC() phase of a Monitor Message (MONMSG); only the difference between status=1 and status=2 need be determined, and only those /failure/ scenarios would effect a Receive Message (RCVMSG) rather than a RCVMSG for every request. As an Exception message, the message received by type would not have been sent FIFO. Receiving messages FIFO is an origin for a common programming error; i.e. "able to receive that message" is often coded improperly, even if seemingly coded correct and even if verified to be correct but only in a too limited set of tests. For an example of that programming error along with discussion of the environment variable, see the following message [and possibly the entire thread]:
<http://archive.midrange.com/midrange-l/200810/msg01387.html>

The Add Environment Variable (ADDENVVAR) request can set the session variable:
ADDENVVAR QIBM_QSH_CMD_ESCAPE_MSG 'Y' /* LEVEL(*JOB) REPLACE(*YES) */