Tshark exit codes - wireshark

I'm currently working with tshark using python subprocess and I want to handle errors in the child process currently.
I can get the sub-process exit code via python's subproccess 'returncode' field, but I can't fined any documentation of tshark exit codes.
I already figured out that 0 means success (no surprise) and 2 means corrupt or unsupported file.
But where there is 0 and 2 there is usually a 1, and there should be more codes.
Does anyone know were I can fined a list of thsark's possible error codes and causes?

Ages ago, I seem to remember somebody suggesting an exit status of 1 for command-line syntax errors and 2 for other errors, and I've followed that convention for a lot of code I've written.
So 1 would be returned if you gave an invalid command-line flag or an invalid capture or display filter or something such as that, and 2 would be returned if it couldn't open a capture device or capture file.

Related

Sending IFS File to Outq Prints Line of "#" Symbols

I am attempting to send a file from IFS to an outq on our AS/400 system. Whenever I do, I get exactly what I send, as well as a line of "#" symbols of varying lengths appended to the end.
Here's the command I'm using:
qsh cmd('cat -c /path/test.txt | Rfile -wbQ -c "ovrprtf file(qprint)
outq(*LIBL/ABCD) devtype(*USERASCII) rplunprt(*no) splfname(test) hold(*no)"
qprint')
The contents of test.txt is just Hello World!
The output I get when I send the command is
Hello World!####################################################################
I have not found any posts online about a similar problem, and have tried changing values and looking for additional switches to get it to work. Nothing I'm doing seems to fix the issue.
Is there a command or switch that I am missing, or is something I have in there already causing this?
EDIT:
I found this documentation which is the first time I've seen this issue mentioned, but it's not very helpful:
“Messages for a Take Action command might consist of a long string of "at" symbols (#) in a pop-up message. (The Reflex automation Take Action command, which is configured in situations, does not have this problem.) A resolution for this problem is under construction. This problem might be resolved by the time of the product release. If you see this problem, contact IBM Software Support.”
The only differences are: 1) this is not a pop-up message, it's printed. 2) I don't believe we use Tivoli Monitoring, although I could be wrong.
Assuming we do use Tivoli Monitoring, what would the solution be? There's no additional documentation past that, and I am not a system administrator, so I can't really make the call to IBM Software Support myself. And assuming we DON'T use it, what else could cause this issue?
I get different results, yet similar. I created a test.txt with Windows Explorer, put in Hello, world!, saved it and tried the script. I got gibberish for the 'Hello, world!' and then the line of # symbols.
My system is 7.3 TR5, CCSID 37 (US English) and my IFS file is CCSID 1252 (Windows English). Results did not change if I used a stream file of CCSID 819 (US ASCII).
I didn't have any luck modifying Rfile switches.
I found that removing devtype(*userascii) produced printed output in plain English without the # symbols. Do you really need *USERASCII? I would think that would be more for a pre-formatted 'print-ready' file like Postscript or the like.
EDIT: some more things to try
I don't understand why *USERASCII is adding those # symbols; it looks like a translation issue.
I tried this and still got the extra ###... You might have to play with the TOCCSID() parameter. Although a failure, it did give me an idea: what if those # symbols are EBCDIC spaces being sent as-is to the *USERASCII print stream? All we'd need is a way to send only the number of bytes in the stream file, without any padding.
CRTPF FILE(QTEMP/PRTSTMF) RCDLEN(132)
CPY OBJ('/path/test.txt') TOOBJ('/qsys.lib/qtemp.lib/prtstmf.file/prtstmf.mbr') replace(*yes)
ovrprtf file(qprint) outq(*LIBL/prt3812) devtype(*USERASCII) rplunprt(*no) splfname(test) hold(*no)
cpyf prtstmf qprint
The data in QTEMP/PRTSTMF is in ASCII; DSPPFM shows that much. It also shows a bunch of spaces: after all, it is a fixed length file. My next step was to write an RPG program to read the stream file and print it, but Scott Klement already did that: http://www.scottklement.com/PrtStmf.zip
This works on my system:
ovrprtf file(qsysprt) outq(*LIBL/abcd) devtype(*USERASCII) rplunprt(*no) splfname(test) hold(*no)
prtstmf stmf('/path/test.txt') outq(abcd)

Unable to read from Agilent 53131A by GPIB in the simple way

Hi I am using LabView 2012, Delphi XE7 and GPIB (I think 488.2), Win7 SP1 and Agilent 53131A.
I used the given NI examples.
NI Labview example - Found in LabVIEW's help - GPIB.vi.
I tried writing and reading to query frequencies from 2 channels and they are successful.
They are are sent and read in succession.
*IDN?
:FUNC 'FREQ 1'
:READ:FREQ?
If they are successful, that meant GPIB for Agilent and NI MAX and driver are successfully installed and configured.
I am also able to use KeySight Connection Expert's to write and read, Again it is also successful.
However, When I used the given NI example in Delphi. Orginally it was saved as Delphi 3 or 4.
I used the Scope Simple example for universal counter. I used it mostly for writing and reading in the simple way. All it needs initialization, read/write and cleanup
I changed the following codes as shown below, in SimpleForm.pas
The detected device is at GPIB0::3::INSTR so, at line 32,
PRIMARY_ADDR_OF_COUNTER = 3;
String to write and read so, at line 132,
CommandBox.Text := '*IDN?';
then it was compiled with no error and run.
String to write was successfully
But upon reading, it was not successfully.
The string output is supposed to be ' HEWLETT-PACKARD,53131A,0,4806'.
The error at the end of the program is as follows below:-
Unable to read from device
ibsta = SC000 <ERR TMO>
iberr = 6 <EABO>
ibcntl = 0
From these readings, I figured out as :-
EABO means abort
I am not familiar with working of GPIB. Kindly advise.
You are correct that EABO is the identifier for an abort. In addition, we can see from ibsta = SC000 <ERR TMO> that the cause of the abort was a GPIB timeout error. I am not familiar with Keysight Connection Expert or your instrument, but since the error was from GPIB timeout, the most likely causes are:
The query was improperly formatted and the instrument thought it was just a write statement with no response needed. (That's probably why the write function had no error, but the read function timed out.)
The query was improperly formatted and the instrument returned an error.
Instrument needs to have 'Talker' capability enabled to send data. (Most instruments do this automatically with queries.)
For more information on generic GPIB commands, see this reference from the folks at National Instruments.

Handling VSAM status code 35 in JCL

My COBOL program reads a VSAM file that may or may not be empty. When the file is empty i get a status code 35 while opening in INPUT/I-O mode. I do not want to handle it in program but in a JCL. Is there any way by which VSAM file can be checked if it is empty or not...if it is not possible through a JCL then can we handle it in program without having to check status code 35?
Add OPTIONAL to the SELECT clause in the FILE-CONTROL paragraph.
SELECT OPTIONAL fdname
ASSIGN TO ddname
...
When you get a starus "35" exit the program with a
MOVE 8 TO RETURN-CODE.
GOBACK.
[example here][1]
http://ibmmainframes.com/about60344.html
You can then test for a non-zero return code in your JCL with a COND=8 on the next step which will only execute when your program detected an empty file.
I seem to recall that you could use IDCAMS to repo the file into a dummy dataset and you would get an RC=4 if it was empty.
That is from memory a few years ago, but then you could put that check in your job stream before running your program and control execution of the next step using the IDCAMS return code.

Use stderr in lua io.popen to determine faulty function call

I'm making a function that can read the metadata of the current song playing in spotify. This is being programmed in lua since it is an implementation for awesome wm. I got the following line to get all the metadata that I can later use.
handle = io.popen('qdbus org.mpris.MediaPlayer2.spotify /org/mpris/MediaPlayer2 org.mpris.MediaPlayer2.Player.Metadata | awk -F: \'{$1=\"\";$2=\"\";print substr($0,4)}\'')
However when Spotify is not running I don't get the expected information and qdbus writes an error to the stderr stream. I wanted to use the fact that qdbus writes to the error stream to determine a fault and stop the program there. (This should also catch any other errors not related to wheter spotify is running or not)
My understanding is that lua popen uses popen3 that can subdivide between stdout and stderr. but all my efforts so far are fruitless and my error stream is always empty. Is it possible to check for a non nil value in the stderr in order to determine a faulty call to qdbus (or awk)?
thanks!
I think you can redirect stderr to stdout in the call to popen like this:
handle = io.popen("somecommand 2>&1")
If you want to differentiate stderr and stdout, you cannot do it with the io library but you can with luaposix. See this answer for instance.
You can checkout juci.exec which I wrote for JUCI webgui. I struggled with the same problem and I ended up using luaposix for this kind of thing when I really need two separate streams. My implementation also gives you the program exit code which is good for testing for errors: https://github.com/mkschreder/juci/blob/master/juci/lua/core.lua

Is there a good way to tell if HandBrakeCLI actually encoded anything?

I'm working on a system to convert a bunch of .mov files to H.264 (using HandBrakeCLI) and webm (using ffmpeg) as the .mov files are created. In general, things are going very well. I'm hung up on a bit of error detection. I want to know if one of the encodings failed so that we can investigate, try again, etc.
To test encoding failure, I copied a text file into a file with a .mov extention, and set the programs about trying to encode it. Naturally, they both fail to encode the file (I'm not sure what "success" would mean in this context...) However, while ffmpeg reports this failure by setting its exit code to 1, HandBrakeCLI sets the exit code to 0, because it exited cleanly. This is consistent with the HandBrakeCLI documentation but it leaves me wondering how I can tell if HandBrakeCLI knows if it failed to encode anything. That same documentation page suggests "If you want to monitor HandBrake's process, you should monitor the standard pipes", so I'm now getting the effect that I want by doing something like this:
HandBrakeCLI --preset 'Normal' --input bad.mov --output out.mv4 2>&1 | grep 'Encode done'
grep then sets its exit code to 0 if it found a match, and 1 if it didn't. But, this seems rather barbaric: for instance, the text "Encode done!" could change in a future release of HandBrake.
So, anyone have a better way to tell if HandBrake encoded something or not?
Some edited shell output is included below for reference...
$ ffmpeg -i 'develqueuedir/B_BH_120409.mov' 'develqueuedir/B_BH_120409.webm'
FFmpeg version 0.6.4-4:0.6.4-0ubuntu0.11.04.1, Copyright (c) 2000-2010 the Libav Developers
[snip]
develqueuedir/B_BH_120409.mov: Invalid data found when processing input
$ echo $?
1
$ HandBrakeCLI --preset 'Normal' --maxWidth 720 --optimize --input 'develqueuedir/B_BH_120409.mov' --output 'develqueuedir/B_BH_120409.mv4'
Output format couldn't be guessed from file name, using default.
[11:45:45] hb_init: starting libhb thread
HandBrake 0.9.6 (2012022900) - Linux x86_64 - http://handbrake.fr
Opening develqueuedir/B_BH_120409.mov...
[snip]
[11:45:45] libhb: scan thread found 0 valid title(s)
No title found.
HandBrake has exited.
$ echo $?
0
Short answer is no , you can find detailed explanation at HandBrake forum https://forum.handbrake.fr/viewtopic.php?f=12&t=18559&p=85529&hilit=return+code#p85529
adddition:
I think that there is a patch from user fonkprop that is rejected by developers , if you really need it contact that guy
Good news! It appears that this feature is about to be implemented in HandBrake-CLI 0.10. As you can read on the roadmap for the 0.10 milestone:
Basic support for return codes from the CLI. (0 = No Error, 1 = Cancelled, 2 = Invalid Input, 3 = Initialization error, 4 = Unknown Error")

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