I am using Eclipse Kepler Service Release 2 , EPIC 0.5.46 and Strawberry Perl 5 version 18 for perl programming. For debugging I am using Eclipse debugger and PadWalker .
I have an interactive perl program that writes to files based on answers provided by the users to multiple prompts. While debugging , every time i change a single line of code I have to rerun the whole program again and provide inputs to every prompt , which is really time consuming.
Is there a way to make changes to the code in a sub routine , in the middle of debugging session such that the instruction pointer resets itself to the first line of that sub routine. This way i do not have to restart the session to recompile the new code.
Appreciate your inputs and suggestions. Thank You!!!
What you want to do can be done, and I've done it many times in Perl myself. For example, see this.
However although what you describe may work (and is a bit dangerous), the way it is generally done a bit different and safer.
First one has to assume a regular kind of command structure like a command processor, or say a web server.
In a command processor or web server, you read a command (or get a web request), perform an action, then read another command, perform another action and so on. From your description, it sounds like you have such a structure.
In my case, I have each debugger command stored as in Perl file. This is helpful not only for facilitating this task, but also for understanding, testing and changing the code.
Given this kind of program structure, instead of trying to change the program counter, you complete the command and at the level where you are about to read a new command, you make the change and then reload the file which changes the code.
The specific Perl construct to do this is called do. Don't use require or use which will load in a Perl file only if that file or module hasn't been previously loaded. In your situation, you want to reload even if it has been loaded before.
So now how do you get to be able to issue a do command? As you suggest, you could do it through a debugger. Assuming you have this overall program stucture as described above, you put the breakpoint somewhere a common point in the caller which loops over things to process, rather than try to change things in indvidual commands.
And you don't even need a debugger to do this! Many web frameworks like Ruby on Rails, have a "development" mode where they save timestamps on files that implement functionality. If the file has changed they issue the "do" command before running the request.
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I have successfully called EXIFTOOL from a batch file, but now I need to call it from a C++ MFC dialog (which needs to pass the results to another program). I have used "CreateProcess" to call EXIFTOOL, which appears to have worked, but I can't figure out how to retrieve the metadata output I requested in the comandline. I know it's possible to do it with Perl and using C++ in Cygwin, but I can't find any info for calling it in native Windows C++. Any tips would be appreciated.
The author of exiftool has a C++ Interface for ExifTool. This uses exiftool's -stay_open option which keeps exiftool running in the background.
Exiftool is not a program you want to call once for every file. The startup time is it's biggest performance hit and calling it once/file can significantly increase processing time. See Exiftool Common Mistake #3.
I've written a simple script that has multiple custom functions stored as modules. I have done it this way because I was always been told that if your function can be reused by other things then it should be a module and not a .\ source include. I'm starting to think that mantra isn't right in my current scenario. I am trying to convert the script to an single .exe so that I can install it as a windows service.
Probably should acknowledge that I understand why you wouldn't want to include system modules like Active Directory or IIS management for the obvious issue that could lead to but I'm only trying to include custom functions in a single disputable non editable way.
I have used PowerGUI in the past but can't find any valid exe's for that since DELL have removed it and from memory, I don't think I've ever used it with a module.
I've tried PS2EXE-GUI and PS2EXE. Both of these make the exe and everything works fine while the modules exist. However, as soon as I put the exe on a server that hasn't got the Modules deployed to it, it fails to run. I thought the compile followed all the dependencies and included them as part of the build into the single exe? That appears to not be the case.
I've also tried the PowerShell Studio 2018 by Sapien, but based on their forums you can't include modules into the complied exe. Which again feels wrong if they are actually just custom functions, but it's the way they've written it.
I see https://poshtools.com/docs/posh-pro-tools/merge-script/ would possibly do what I need but that's chargeable and it looks like it actually merges all the content back into a single file. Given the time pressure I'm starting to think I'll have to pay if there are really no other better options. I just don't have time to join everything together manually and I can't help thinking there is a better way I'm missing!
Can anybody please suggest other options?
Could I also get clarification around my original mantra (functions go in modules...)?
"No, never!" or "Yes, always!" or "It's just wrong in this scenario."
I'm building a program that acts on files that it has to download from one of my company's servers. We have several million of these. For instance, my normal invocation could be:
python my_script.py file-id
And then my_script.py will go download file-id and do its work on it.
It's useful to be able to specify one fixed file to download and act on while I make changes to our code, but when it comes to testing at scale, I'll usually find out that maybe a dozen files couldn't be processed correctly, and I need to go and debug our program with it.
For this purpose, editing the settings.json file works, but it's kind of cumbersome that I have to change the parameter, save, run, and revert every time I just want to test a new input.
Is there a way that I pass an argument to a debug configuration as I start debugging, instead of having to change the settings.json file?
I am using a web form I created as an interface to query a MySQL database. I have written some
perl CGI scripts to process the queries. But I am not getting the desired output, so I need to
debug the scripts. How do I do that? I mostly use Eclipse for debugging perl, but now I have the
web form parameters (checkboxes, listboxes) as input to the script. Is there any way I can pass
in the inputs from the web page and then debug the script in Eclipse? Or is there any other way
of debugging in this case? Hope I have made myself clear. Thanks.
I use this Perl module for CGI debugging. It lets you capture all data sent to a CGI script, when running from a normal browser. It then lets you "replay" the script from anywhere (command line, within a debugger) using the captured data.
CGI::Inspect looks promising, though I haven't tried it yet myself.
Using Devel::DumpTrace during a normal CGI session (with the data being logged to a file, via DUMPTRACE_FH) is a way to do in-depth debugging, without using an actual debugger.
Yes, of course you can use Apaches error log to do debugging; which a very lazy but efficient way to work.
You mention you use Eclipse so I assume you also use the EPIC plug-in for Perl development. Check out this chapter on how to configure Eclipse/EPIC for debugging CGI:
http://www.epic-ide.org/guide/ch06s02.php
I would hope Eclipse has a way to simulate CGI.
I use ActiveState's Komodo IDE, and it can simulate CGI (including input params), so I can recommend that as a good tool for this purpose. The IDE is NOT free, though, but consider this an investment if you're going to be doing this a lot. (I'm NOT affiliated with ActiveState - just a happy customer.)
It's not clear what exactly you want to debug, but a few tips:
When running under Apache, warnings go to the error.log, so you could follow your variables there.
The CGI.pm module allows you to run CGI scripts from the command-line (with parameters).
if you have a hypothetical CGI program written in perl, called webawesome.pl and you want to pass it two parameters: name and age, you can use a shell command like this:
prompt> perl -d webawesome.pl name=sifl age=21
Now you're in the perl debugger and you can step through your program, and the key/value pairs from the command line will be loaded as form parameters by CGI.pm
Setting these command line switches in Eclipse is left as an exercise to the reader, as I am an unabashed vi user, and haven't use eclipse in two or three years. I know there's dialogs to set run/debug options.
You can use Firebug or Fiddler to watch your requests made from the form, to ensure you are sending exactly what you think you are. You can also open a file open(fh,">>debug.txt") and print out the sql calls that you are making to a log file. I would also suggest learning about Data::Dumper which will print out objects prettily so you can see their structure.
I've been searching for this for awhile now, and I am not sure if I am just not using the correct search terms or if the answer is really that hard to find.
What I am trying to do is to create a new Windows service for a game server from a batch file, and then have a task run another batch file every 30 minutes or more that would run two commands on the game server's command line and do some file work.
Specifically, I am running a Minecraft server using Bukkit for a gaming community I help run, and I want to make sure that the thing is always up unless I specifically tell it to stop (like a service). Bukkit is run directly from a batch file and has it's own command line thing running on it.
I am told that you CAN run this type of thing as a service, but the command line will be hidden from view and/or interaction. This is the second part of my query. I have a handy little backup.bat file that copies all the world files and userdata files into a backup directory, 7zips it, and deletes the directory. The only thing is, is that Minecraft likes to always have the worlds' region files open and writing at all times, meaning that it could cause map corruption if I just run it straight off. To compensate, I need to run the command "save-off" on the server to disable the file hooks temporarily, run the backup, and as soon as it finishes, run "save-on" so that the game can continue without lost data.
What I would like to know about this second one is, is it possible to interface with the game service through a batch file, or do I need to create an application to do that? If the latter, how exactly does one go about doing that? I have moderate C++ knowledge (up through my second OO-C++ course in college), and can possibly learn another language if absolutely necessary.
So, in short, two questions:
1. Is it possible to, and how to run a BAT file as a Windows Service?
2. How to interface with said service via BAT files, and if not possible, what kind of application do I need to write (redirection to or writing a tutorial works for me).
Thank you in advance for any and all help!
Old question, user account doesn't seem active on SO anymore, but hey, if you stumble upon this because you have a similar problem:
Since we are speaking about a Bukkit Minecraft server, turn to the "Essentials" plugin for Bukkit.
It now includes a Backup function that does exactly what the OP asks for, namely stop the save so the files can be manipulated without corruption, launch a script, then starts again.
The script can be a backup one (examples provided in the linked page) but can be used to run any operation on the world's files.