I am using a bash script to run a number of application (some repeatedly) on a Windows machine through cygwin. The script contains commands to launch those applications, line by line. Most of these applications run for many minutes and many times I have observed that the i+1 th application is not being started even after i th application is completed. In such cases, if I press enter in the cygwin console on which the bash script is running, the next application starts running. Is it because of any issue with bash on cygwin? Or is it an issue with the Windows OS itself? Have any of you observed such an issue with bash + cygwin + Windows?
Thanks.
I think I have seen this before.
Instead of
somecommand
try
somecommand </dev/null
If that doesn't work, try
cmd /c somecommand
Or experiment with other redirections, e.g.
somecommand >/dev/null
Sounds like you may have a problem with your shell script encoding; DOS (and Windows) uses CR+LF line endings, whereas Linux uses LF endings. Try saving the file as LF.
What might also be going on:
When I was running Cygwin on a school laptop, I encountered a dramatic slowing of shell scripts vs. when they were running in a native Linux environment. This was especially apparent when running a configure script from GNU Autotools.
Check your path for slow drives. (From the Cygwin FAQ):
Why is Cygwin suddenly so slow?
If suddenly every command takes a very long time, then something is probably attempting to access a network share. You may have the obsolete //c notation in your PATH or startup files. Using //c means to contact the network server c, which will slow things down tremendously if it does not exist.
You might also want to check whether you have an antivirus program running. Antivirus programs tend to scan every single executable file as it is executed; this can cause problems for even simple shell scripts that run hundreds or even thousands of individual programs before they run their course.
This mailing list post outlines what is needed to pseudo-mount the main /usr/bin directory as cygexec. I'm not sure what that does, but I found it helped.
If you're running a configure script, try the -C option.
Hope this helps!
Occasionally, I'll get this behaviour because I have accidentally deleted the 'she-bang' at the top of the script, that is, deleted the #!/bin/bash on the first line of the script.
It's even more likely for this to happen when a parent shell script calls a child script that has the she-bang missing!
Hope this helps.
A bit of a long shot, but I have seen some similar behaviour previously.
In Windows 2000, if any program running in a command prompt window had some of it's text highlighted by the cursor, it would pause the command running, and you had to press enter or clear the highlighting to get the command prompt to continue executing.
As I said, bit of a long shot, but accidental mouse clicks could be your issue...
Install cygwin with unix style line breaks and forget weird problems like that.
Try saving your script as "the-properly-line-broken-style" for your cygwin. That is, use the style you specified under installation.
Here is some relevant information:
https://stackoverflow.com/a/7048200/657703
Related
I run calculations on Windows for hours and would like to have the calculation report/log inside the interactive IDLE/shell window be saved to a file at the end by a command.
Would be nice to exit() and close the window too.
As much as I like Linux, this is an Unattended Windows machine, hence, some modules/commands are not available, sadly, and the ability to install other software is limited.
The fact that the developers did not think of a command to save the transactions within the IDLE/shell is surprising.
I know in some environments you can direct the output of a job, like a report to another text file by using the key -o, --o, --output, > to a text file. Surprisingly Python does not support anything like that!
Any help would be appreciated
Thanks
Windows Command Prompt supports stdout redirection and probably stderr redirection. I just tested python -c "print(test)" > F:/dev/tem/out.txt and the print out went to out.txt. Replace -c "print('test') with script.py and the same should happen. Piping stdout of one program to stdin of another might work. You might be able to chain programs with a .bat file. PowerShell likely is more powerful and flexible, but I have never used it.
I am not completely clear on what you are asking, but I hope the following answers your questions.
Python runs in 2 modes: batch and interactive. Interactive mode is intended for ephermeral interaction with a human. Batch mode is for unattended computation, with occasional screen messages, but with most results sent to a file other than the screen. Both modes are combined when you run python -i xyz.py. The file is first run in batch mode, and then Python shifts to interactive mode.
It sounds like you should be using batch mode rather than either Python's or IDLE's interactive mode. If your code runs from IDLE, you should be able to run it directly with the same python.exe that you used to run IDLE. There are exceptions, of course, if one makes one's code dependent on running within IDLE, but this is unlikely to be an accident or to be needed for unattended running.
The IDLE Shell simulates interactive Python. When a file is run from an editor window, IDLE simulates python -i file-being-edited.py, with screen output going to Shell. In either case, an interactive user can save the contents of Shell with the File => Save As menu command. So there is such a command. There are also close window and exit commands and shortcuts.
In IDLE's intended use, as an interactive python learning and program development environment, there is no need from for a program to issue these commands. To save data in a file, a program can open a file and write data directly.
Try to see if you can install Jupyter Notebook (not separate software, but just a python module)
pip install jupyter
Jupyter notebook is highly helpful for saving and sharing your code. It can be used as both a shell and as a script editor.
I am creating an installation using InstallShield 2018 in windows 10. I need to execute a script file (.sh) in Ubuntu from a function in Installscript. I tried the following but it did not work:
szCmdPath = "C:\\Users\\Admin\\AppData\\Local\\Microsoft\\WindowsApps\\Ubuntu.exe";
szCmdLine = ". /mnt/d/test.sh";
LaunchAppAndWait( szCmdPath, szCmdLine, WAIT);
However I can execute the exact same file in Ubuntu Terminal and it works great. I did turn on Window sub system for Linux and install Ubuntu on windows. Why is this happening? Why can I run cmd.exe from installscript but not Ubuntu?
Thank you in advance.
EDIT 1: if I pass an empty string as parameter, Ubuntu is start and waits for my input commands. But when I pass the path to my script file, nothing happened except a flash of the terminal console before my installation goes on running.
From my reading, wsl and ubuntu differ slightly. It looks like wsl is a bit magical and occasionally similar to bash -c or ubuntu -c, whereas you can consider Ubuntu.exe as somewhat equivalent to /bin/bash.
If you try to run /bin/bash . /mnt/d/test.sh from a bash prompt, things don't go well. So the correct approach will depend on the contents of your script and what you need to happen. I think one of the following options are the most likely:
remove . from your command; instead run ...\Ubuntu.exe /mnt/d/test.sh
add -c to your command; instead run ...\Ubuntu.exe -c . /mnt/d/test.sh
Note that %LOCALAPPDATA%\Microsoft\WindowsApps\Ubuntu.exe is a special file (zero bytes), so it's also plausible that it needs some special handling. For instance, maybe it requires a 64-bit caller. If that's the case, you may need to wrap it in a call through a 64-bit cmd prompt. My quick tests don't show this as likely, however, so I think it will work without this extra indirection.
I am running a cygwin shell under windows 10 in which I start a "screen" session and under that the cygwin version of emacs (24). If I do M-xshell, it starts a cygwin (bash) shell just fine. So for most of my programming I'm happy. However, if within the cygwin shell I run "cmd" to get a "DOS prompt". I get this weird error message from emacs, "Waiting for process to die" (and some more text about hitting ctrl-g). I also get the same message, if I set the shell to be cmd by setting "explicit-shell-file-name" when I run shell. (That's actually what I tried first.)
Now, if hit C-g (perhaps twice?), the shell appears and cmd appears to be running, but I'm not certain of the state of things.
Has anyone else seen this error message? Googling for it returned nothing useful. Is there some incompatibility between the cygwin build of emacs and running cmd? Any hints on how to get around this problem?
Alternately, is there any way to send "builtin?" "DOS" commands (like MKLINK) under bash to a DOS box? How about running .cmd files? I really hate running a separate DOS box (not under emacs) and sometimes I need to do "DOS" things (and usually want the output captured in an emacs buffer).
I just realized that i cannot execute .sh scripts anymore on my debian.
It used to work fine. All .sh files are +x chmodded and used to work fine.
Suddenly, once i execute: ./test.sh system hangs.
I am able to stop this via ctrl+c, but script never executes.
Steps did so far was to restart my VPS.
Any ideas?
I am pretty sure shell scripts are still working on your machine, because if they weren't, you would not be able to complete any boot cycle.
If I suppose you are facing problems with your homemade scripts, then you should probably check your shebang line (#!/bin/sh for example) to see if anything unusual was used there.
New scripts are using a dispatcher to interpreters:
`#!/usr/bin/env bash` #lends you some flexibility on different systems
`#!/usr/bin/bash` #gives you explicit control on a given system of what executable is called
The difference between “#! /usr/bin/env bash” and “#! /usr/bin/bash”?
I have made a few python scripts, but is there an easier way to run them? I am using cygwin.
python "C:\Users\Desk\Dropbox\scripts\wsort.py" > data11414_unsorted.txt < data11414_sorted.txt
I want something like this (not typing the path name or "python"):
wsort > data11414_unsorted.txt < data11414_sorted.txt
where wsort is a link to my real wsort.py
Add a
Shebang
to the script
#!/bin/python
then invoke like this
wsort.py > data11414_unsorted.txt < data11414_sorted.txt
First, your question has a Windows-style path (backslashes, beginning with C:) rather than a Cygwin path (/cygdrive/c/Users/Desk/Dropbox/scripts/wsort.py). That implies you're not actually using Cygwin, or if you are, you're ignoring a bunch of warnings.
The below assumes you're using Cygwin Bash (which should be what you get if you start Cygwin Terminal from the Start Menu) and Cygwin Python (which you've installed using Cygwin's setup.exe, not a Windows Python installer). If your not, you're making life more difficult for yourself than you need to.
That out the way, there's a bunch of steps you need to take:
First, make the script executable. Use the chmod command for that, from a Cygwin Bash shell:
chmod +x /cygdrive/c/Users/Desk/Dropbox/scripts/wsort.py
Second, tell the system how to execute it. Add the following line to the top of the script:
#!/bin/python
(That's a "shebang". Python sees it as a comment, so doesn't do anything with it, but Cygwin and other Linux-like systems will use that line to see which program to run the script with. In this case, Python.)
Third, make sure your line endings are correct. Cygwin expects Linux line endings and will fail without them. This may not be a problem, but there's no harm in doing this. Run the following command:
dos2unix /cygdrive/c/Users/Desk/Dropbox/scripts/wsort.py
At this point, you'll be able to call the script by specifying the full path to it in Cygwin. You can't yet run it without specifying where the script is explicitly.
The fourth step is making sure the script is "in your path", ie in one of the folders where Cygwin looks for scripts to run. There are lots of ways to do this, but the most sensible is probably to just add your scripts directory to your path. The following command will add your scripts directory to your path whenever you start a new Cygwin session:
echo 'PATH="/cygdrive/c/Users/Desk/Dropbox/scripts:$PATH"' >>~/.bashrc
You will need to restart your Cygwin terminal for that to take effect, however.
At that point, you'll be able to run the script in Cygwin just by typing wsort.py (and thus use it with redirections and so forth as in your question).
Finally, to be able to call it simply as wsort, there's a number of options. The obvious one is just renaming the file. More usefully (and without copying the file or doing anything liable to break with Dropbox syncing things), try creating an alias:
echo 'alias wsort=wsort.py' >>~/.bashrc
Again, you'll need to restart your Cygwin terminal for that to take effect.
Maybe use an alias ?
alias wsort = "Command_Used"