I'm trying to create a bash script to run an AppImage on startup with certain flags.
This is the normal way to run through terminal on the folder where the appimage is located:
$ ./conky.AppImage -c $HOME/Downloads/Pleione/Pleione.conf &> /dev/null &
And I'm trying to put that in a bash script. I have this:
#!/bin/bash
cmd= $(echo /home/edbanshee/Downloads/conky.AppImage)
$cmd
And of course, it runs the AppImage, however I have no idea how to include the -c flag with the parameters. To my very limited knowledge, I tried something like:
#!/bin/bash
cmd= $(echo /home/edbanshee/Downloads/conky.AppImage)
$cmd -c $HOME/Downloads/Pleione/Pleione.conf &> /dev/null &
To no avail so I guess thats not how that works (sorry if these are silly attempts, I am learning by trial and error)
Yet i can't seem to find any information about bash scripting on how to accomplish this, or maybe I'm bad at looking. I found tutorials regarding getops, but as I understand it, that works to pass flags onto the script itself, which doesn't seem to be what I'm looking for, or am I understanding it incorrectly?
Any suggestions?
Related
Been banging my head against the wall for a couple hours so time to call in the experts. Writing a small script to run some reports on one of my office's systems and I was asked to take care of a Bash script for it. The program called "auto_rep" takes various options such as "-t" to run one task (to generate one type of report) and a "-1" to exit after one task. The options are separated by spaces when running the command from command-line. The command works directly from command line but I cannot get it to work from a script...
Below is the snippet of code causing me issues:
cmd=$(auto_rep -t createfin1report -1)
echo "running ${cmd} command..."
echo
eval $cmd
The problem is when I run the script, only the "auto_rep" part of the command (from $cmd variable) is run; basically running the program without any options. And it creates tons of reports without the "-t createfin1report -1" part of the command (yikes!). Glad I only tried it on our test system.
Anyone have any tips to help me out? Is my approach way off? BTW - had tried just storing the command in a non-array (cmd="auto_rep -t createfin1report -1") and that was causing me other headache with a "command not found" errors :)...
Thanks in advance!
Save output to an array, then executing this array.
declare -a cmd
cmd=( $(auto_rep -t createfin1report -1) )
echo Executing: "${cmd[#]}"
"${cmd[#]}"
Please make sure the output is a valid command, and spaces have been correctly placed in double-quotes.
Is it possible to check a bash script syntax without executing it?
Using Perl, I can run perl -c 'script name'. Is there any equivalent command for bash scripts?
bash -n scriptname
Perhaps an obvious caveat: this validates syntax but won't check if your bash script tries to execute a command that isn't in your path, like ech hello instead of echo hello.
Time changes everything. Here is a web site which provide online syntax checking for shell script.
I found it is very powerful detecting common errors.
About ShellCheck
ShellCheck is a static analysis and linting tool for sh/bash scripts. It's mainly focused on handling typical beginner and intermediate level syntax errors and pitfalls where the shell just gives a cryptic error message or strange behavior, but it also reports on a few more advanced issues where corner cases can cause delayed failures.
Haskell source code is available on GitHub!
I also enable the 'u' option on every bash script I write in order to do some extra checking:
set -u
This will report the usage of uninitialized variables, like in the following script 'check_init.sh'
#!/bin/sh
set -u
message=hello
echo $mesage
Running the script :
$ check_init.sh
Will report the following :
./check_init.sh[4]: mesage: Parameter not set.
Very useful to catch typos
sh -n script-name
Run this. If there are any syntax errors in the script, then it returns the same error message.
If there are no errors, then it comes out without giving any message. You can check immediately by using echo $?, which will return 0 confirming successful without any mistake.
It worked for me well. I ran on Linux OS, Bash Shell.
I actually check all bash scripts in current dir for syntax errors WITHOUT running them using find tool:
Example:
find . -name '*.sh' -print0 | xargs -0 -P"$(nproc)" -I{} bash -n "{}"
If you want to use it for a single file, just edit the wildcard with the name of the file.
null command [colon] also useful when debugging to see variable's value
set -x
for i in {1..10}; do
let i=i+1
: i=$i
done
set -
For only validating syntax:
shellcheck [programPath]
For running the program only if syntax passes, so debugging both syntax and execution:
shellproof [programPath]
Bash shell scripts will run a syntax check if you enable syntax checking with
set -o noexec
if you want to turn off syntax checking
set +o noexec
There is BashSupport plugin for IntelliJ IDEA which checks the syntax.
If you need in a variable the validity of all the files in a directory (git pre-commit hook, build lint script), you can catch the stderr output of the "sh -n" or "bash -n" commands (see other answers) in a variable, and have a "if/else" based on that
bashErrLines=$(find bin/ -type f -name '*.sh' -exec sh -n {} \; 2>&1 > /dev/null)
if [ "$bashErrLines" != "" ]; then
# at least one sh file in the bin dir has a syntax error
echo $bashErrLines;
exit;
fi
Change "sh" with "bash" depending on your needs
I have never written a script, so bear with me. What I need to do, is make two scripts that I can click on from the desktop, will both open their own terminal (And stay open until I manually close it) and run the given lines.
For the first one, I have to manually run this:
cd home/pi/PiBits/ServoBlaster/user
sudo ./servod
For the second:
cd ~/scratchClient
python crs/scratchClient.py -c servoblaster
How would I do this? I read a few things about putting xterm -e and such in front of it, but none of that works for me...
By the way, this will be used on Raspbian Linux.
EDIT, this worked for me:
Link: ubuntuforums.org/showthread.php?t=1336228 The line that was used: gnome-terminal --execute bash -c "/path/scriptname ; bash"
You just need to add a shebang, which means putting this in the first line of the script:
#!/bin/sh
This causes the bourne shell to be used to interpret the script, this is (probably) the same interpreter that runs when you are in your terminal. Then you should make the script executable chmod +x <script>
Try this.
xterm -hold -e 'cd /home/pi/PiBits/ServoBlaster/user
sudo ./servod' &
and
xterm -hold -e 'cd /home/pi/scratchClient
python crs/scratchClient.py -c servoblaster' &
If it doesn't work, perhaps you should explain in what way this fails. If it works, you can add a shebang in front, save them in files, chmod +x those files, and click away to your heart's content (or perhaps acquire a more sophisticated taste where you simply run these as background jobs without any xterm or other anxious GUI).
Solution was to use gnome-terminal... Found an UbuntuForums post with a similar question such as mine.
gnome-terminal --execute bash -c "/path/scriptname ; bash"
i have very simple shell script
#!/bin/bash
cp -rf /var/www/ksite/app2/* /var/www/ksite/app
echo "----"
echo "done"
but seems cp command fails
if i execute
cp -rf /var/www/ksite/app2/* /var/www/ksite/app
from terminal everything work ok. Can someone tell me how to include cp in shell script?
Thanks
We seem to have doubt as to how this script fails. If there is no error message then this is a strange one. I suggest:
On the command line (which works), do a which cp
Whatever the reply, then copy that and use it as the cp in the script (e.g. /bin/cp)
Check the widcard expansion, run your script with bash -x script-name and see if you get what you expect.
echo $? after the copy in the script - if it is zero then it (thinks it) worked.
Do a ls -ld /var/www/ksite/app from your script, maybe someone set a symbolic link?
If it still fails, source the script from the command-line and see if that works . script-name
Double check that the copy did actually fail! (maybe that should be step 1.)
Make sure you really have bash at /bin/bash. I think a batter hash bang is:
#!/usr/bin/env bash
This uses the env command to locate the bash binary and set the environment.
I had similar problem. What helped me:
I used windows and putty to write script, so I had \r\n at the end of lines. Be sure, you have only \n symbol.
I copied files and the only way it worked for me at script was cp <source_dir>/fileName <dest_dir>/fileName whereas at command line cp <source_dir>/fileName <dest_dir> worked well too.
Just covering all the bases .. do the permissions vary between the excutions .. i.e. do you execute one with sudo/root privileges, the other as user (unlikely, but thought I'd ask since we don't know what the exact error is)
Similar issue to Vladmir where the script was created in Windows. I created a new file "my_bash_script.sh" in the linux environment using VIM, then read the contents of my script into the file:
:r file_made_in_windows.sh
Then I saved, closed, then set the file as executable:
chmod 744 my_bash_script.sh
From there, I ran the script:
./my_bash_script.sh
...and it worked. What a weird issue. I was confounded for a moment.
Is it possible to check a bash script syntax without executing it?
Using Perl, I can run perl -c 'script name'. Is there any equivalent command for bash scripts?
bash -n scriptname
Perhaps an obvious caveat: this validates syntax but won't check if your bash script tries to execute a command that isn't in your path, like ech hello instead of echo hello.
Time changes everything. Here is a web site which provide online syntax checking for shell script.
I found it is very powerful detecting common errors.
About ShellCheck
ShellCheck is a static analysis and linting tool for sh/bash scripts. It's mainly focused on handling typical beginner and intermediate level syntax errors and pitfalls where the shell just gives a cryptic error message or strange behavior, but it also reports on a few more advanced issues where corner cases can cause delayed failures.
Haskell source code is available on GitHub!
I also enable the 'u' option on every bash script I write in order to do some extra checking:
set -u
This will report the usage of uninitialized variables, like in the following script 'check_init.sh'
#!/bin/sh
set -u
message=hello
echo $mesage
Running the script :
$ check_init.sh
Will report the following :
./check_init.sh[4]: mesage: Parameter not set.
Very useful to catch typos
sh -n script-name
Run this. If there are any syntax errors in the script, then it returns the same error message.
If there are no errors, then it comes out without giving any message. You can check immediately by using echo $?, which will return 0 confirming successful without any mistake.
It worked for me well. I ran on Linux OS, Bash Shell.
I actually check all bash scripts in current dir for syntax errors WITHOUT running them using find tool:
Example:
find . -name '*.sh' -print0 | xargs -0 -P"$(nproc)" -I{} bash -n "{}"
If you want to use it for a single file, just edit the wildcard with the name of the file.
null command [colon] also useful when debugging to see variable's value
set -x
for i in {1..10}; do
let i=i+1
: i=$i
done
set -
For only validating syntax:
shellcheck [programPath]
For running the program only if syntax passes, so debugging both syntax and execution:
shellproof [programPath]
Bash shell scripts will run a syntax check if you enable syntax checking with
set -o noexec
if you want to turn off syntax checking
set +o noexec
There is BashSupport plugin for IntelliJ IDEA which checks the syntax.
If you need in a variable the validity of all the files in a directory (git pre-commit hook, build lint script), you can catch the stderr output of the "sh -n" or "bash -n" commands (see other answers) in a variable, and have a "if/else" based on that
bashErrLines=$(find bin/ -type f -name '*.sh' -exec sh -n {} \; 2>&1 > /dev/null)
if [ "$bashErrLines" != "" ]; then
# at least one sh file in the bin dir has a syntax error
echo $bashErrLines;
exit;
fi
Change "sh" with "bash" depending on your needs