transmission-remote's exit code should be nonzero on failure

[gaa]

It is a common practice to return non-zero exit code if command execution was failed.

Test 1:

$ transmission-remote torrenthost -n $user:$passwd -a /tmp/nonexistent-file torrenthost:9091 responded: "invalid or corrupt torrent file" $ echo $? 0

Expected results:

Exit code is non-zero

Actual results:

Exit code is zero

---

Test 2:

$ transmission-remote torrenthost -n $user:$passwd -a tmp/nonexistent-file 10.22.0.1:9091 responded: "success" $ echo $? 0

Results:

OK, exit code is zero

[gaa]

It is a common practice to return non-zero exit code if command execution was failed.

---

Test 1:

$ transmission-remote torrenthost -n $user:$passwd -a /tmp/nonexistent-file
torrenthost:9091 responded: "invalid or corrupt torrent file"
$ echo $?
0

Expected results:

Exit code is non-zero

Actual results:

Exit code is zero

---

Test 2:

$ transmission-remote torrenthost -n $user:$passwd -a tmp/nonexistent-file
10.22.0.1:9091 responded: "success"
$ echo $?
0

Results:

OK, exit code is zero

[charles]

What is the use case for this change?

[gaa]

I have shell-script that bound to torrent files in firefox.

reply="`transmission-remote "$HOST":"$PORT" -n "$USER":"$PASS" -a "$torrentFile"`"
echo "$reply" | grep -q success
if [ $? = 0 ]
then
    kdialog --title "$0" --msgbox "Torrent has been successfully added!"
    rm "$torrentFile"
else
    kdialog --title "$0" --error "Unable to add torrent:\n$reply"
    rm "$torrentFile"
    exit 1
fi

Corrently I need to parse command result. But it is not reliable: output string can be changed in a future releases and/or can be translated to my language (my locale is not en_US). Checking exit code is a more reliable and common practice.

If exit code will be adjusted, my script can be rewritten in the following manner:

transmission-remote "$HOST":"$PORT" -n "$USER":"$PASS" -a "$torrentFile"
if [ $? = 0 ]
then
    kdialog --title "$0" --msgbox "Torrent has been successfully added!"
    rm "$torrentFile"
else
    kdialog --title "$0" --error "Unable to add torrent:\n$reply"
    rm "$torrentFile"
    exit 1
fi

[charles]

I guess that's reasonable.

Could you cook up a patch for remote.c?

[gaa]

I think that implementing this enhancement will require RPC protocol enhancement because command execution result are not sent inside server's responce (only string message are sent). I does not have enough code knowledge to implement that.

[charles]

you don't need to change the RPC protocol. The response's "result" value MUST be "success" on success, so you can just test for that and return nonzero when it's not "success".

only remote.c needs to be changed for this ticket.

[charles]

gaa: are you going to patch remote.c to do this?

[gaa]

Sorry, I am too busy now. May be on the next week.

[charles]

gaa: any progress on this?

[adurity]

Patch file for this enhancement

[adurity]

I have attached a patch file that I believe satisfies this enhancement. It returns EXIT_SUCCESS when all is normal, and returns EXIT_FAILURE when something goes wrong. This mechanism is POSIX compliant and thus portable.

[charles]

thanks adurity!