executing shell command using shell script - linux

I have shell command ./cherrypicker.sh input.txt which works fine in terminal.
But I want to execute few more command before and after this command like
echo "some text" > input.txt
./cherrypicker.sh input.txt
result < input.txt.response
rm input.*
So I put all this in another shell file, alls.sh and tried to execute it like this
./alls.sh
which says
bash: ./test.sh: Permission denied
then
sudo ./alls.sh
which gives
sudo: ./test.sh: command not found
what is the correct way?

Add execution rights to the script:
chmod +x test.sh
The second problem is related to the path. cd to the directory or use the full path (use whichever is more appropriate for the task).

You might want to make sure that test.sh is actually executable by doing
chmod 0700 /path/to/test.sh
And then run it without sudo.
A note on sudo: it is not muckrake to get all your problems out of your way. ;) Think of it is rather a foil to punctually and elegantly make your point clear. ;)

Related

How to Start a Bash Script with Fewest Keystrokes

To fire a shell script from the command line, instead typing this at a Linux/Unix command line:
~$ <shell> tale.sh
In my case, using bash:
~$ bash tale.sh
How do you setup profile/defaults/scripts so that the command will run with just:
~$ tale
I know this can be different for different shells. I need the answer for bash.
This is the whole listing for ~/tale.sh:
#! /bin/bash
tail -f ~/lp/_logs/error.log
That file, ~/lp/_logs/error.log, is a PHP error log.
First, you need to rename your script:
mv tale.sh tale
Then, there may be two additional steps:
1) Set the executable bit on your script:
chmod +x tale
2) Make sure your script is in your PATH. For example, you could place it in your bin directory (assuming your bin directory is in your path):
mv tale ~/bin
Once all this is in place your script will run from anywhere, whichever shell you are using.
There is an alternative approach called "alias" which could be use.
alias tale="./tale.sh"
or
alias tale="tail -f ~/lp/_logs/error.log"
This lasts until session is not terminated. It can be persists by making an entry in .bashrc or .bash_aliases file.
You can try with the below one line command :)
chmod +x tale.sh && bash tale.sh;

Bash script not running

I am trying to learn bash scripting and I'm using Ubuntu Linux. I have written a simple Bash file to count the number of files in current directory. I have written the following script in a file:
#! /bin/bash
ls -1 | wc -l
And saved the file with the name countFile.
But when I am trying to execute the script using ./countFile it is not executing. It shows the following error:
bash: ./countFile: Permission denied
The countFile is in my home directory so why I haven't the permission. Am I doing something wrong or missing some important thing? Moreover, the ls -1 | wc -l command gives me the correct output when I run it from the terminal.
So how can I run the countFile script?
While you are giving like this,
./countfile
You have to make that file as executable using chmod.
chmod +x countfile
Or else you can use the other interpreter like this.
sh countfile
while executing the file we need a execute permission for that file,
we can change the permission or
we just run as
. countfile
hew . will represent the current working shell

bad interpreter: Permission denied in shell scripting ls ubuntu

I am quite new to the shell scripting.
So I am writing the shell script to list all files available in the directory using ls command.
but I am getting the error bad interpreter: Permission denied
#!/home/gaurav
echo "Welcome bash shell scripting"
ls
echo "this complets the listing of directories"
I want to get the list of "/home/gaurav" this path
Thanks
This line...
#!/home/gaurav
... means "instead of using /bin/bash, use /home/guarav as the program to run this file". This is not what you want. What you want is either:
cd /home/gaurav # at the top, or
ls /home/gaurav # between echoes
Problem is this line:
#!/home/gaurav
This is called shebang and it should be the bash/shell interpreter like this:
#!/bin/bash
one that interprets and executes your script. Since /home/gaurav is not a valid interpreter you're getting that error.
You probably want this in your script:
ls /home/gaurav
to list all files/directories in /home/gaurav path.
Either add #!/bin/bash or #!/bin/sh instead of #!/home/gaurav line while starting script.
Because, while running shell script, you have to give path of which bash or sh are you going to run to execute that script.

cp command won't run if executed from shell script

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.

Bash script: bad interpreter

Question: I get this error message:
export: bad interpreter: No such file or directory
when I execute this bash script:
#!/bin/bash
MONO_PREFIX=/opt/mono-2.6
GNOME_PREFIX=/opt/gnome-2.6
export DYLD_LIBRARY_PATH=$MONO_PREFIX/lib:$DYLD_LIBRARY_PATH
export LD_LIBRARY_PATH=$MONO_PREFIX/lib:$LD_LIBRARY_PATH
export C_INCLUDE_PATH=$MONO_PREFIX/include:$GNOME_PREFIX/include
export ACLOCAL_PATH=$MONO_PREFIX/share/aclocal
export PKG_CONFIG_PATH=$MONO_PREFIX/lib/pkgconfig:$GNOME_PREFIX/lib/pkgconfig
PATH=$MONO_PREFIX/bin:$PATH
PS1="[mono-2.6] \w # "
But the bash path seems to be correct:
asshat#IS1300:~/sources/mono-2.6# which bash
/bin/bash
asshat#IS1300:~# cd sources/
asshat#IS1300:~/sources# cd mono-2.6/
asshat#IS1300:~/sources/mono-2.6# ./mono-2.6-environment
export: bad interpreter: No such file or directory
asshat#IS1300:~/sources/mono-2.6# ls
download mono-2.4 mono-2.4-environment mono-2.6 mono-2.6-environment
asshat#IS1300:~/sources/mono-2.6# cp mono-2.6-environment mono-2.6-environment.sh
asshat#IS1300:~/sources/mono-2.6# ./mono-2.6-environment.sh
export: bad interpreter: No such file or directory
asshat#IS1300:~/sources/mono-2.6# ls
download mono-2.4-environment mono-2.6-environment
mono-2.4 mono-2.6 mono-2.6-environment.sh
asshat#IS1300:~/sources/mono-2.6# bash mono-2.6-environment
asshat#IS1300:~/sources/mono-2.6#
What am I doing wrong? Or is this a Lucid Lynx bug?
I did chmod + x
The first line, #!/bin/bash, tells Linux where to find the interpreter. The script should also be executable with chmod +x script.sh, which it appears you did.
It is highly likely that you created this file with a windows editor, which will place a <cr><lf> at the end of each line. This is the standard under dos / windows. OS X will place a <cr> at the end of each line. However, under Unix / Linux, the standard is to just put a <lf> at the end of the line.
Linux is now looking for a file called /bin/bash<cr> to interpret the file,
where <cr> is a carriage return character, which is a valid file character under Linux. Such a file doesn't exist. Hence the error.
Solution: Edit the file with an editor on Linux and get rid of the extra <cr>. One tool that usually works when the file is edited on Windows is dos2unix.
Could the script be using Dos newlines?
Try running dos2unix on it.
It looks like things have been configured to override the export builtin somehow. This can be done via an exported function or the enable builtin, for example. Try putting type export in the script to check. If you are setting BASH_ENV, you probably shouldn't.
If bash is called as sh, it enables POSIX mode and does not allow export to be overridden with a function, as required by POSIX. Likewise, most other shells installed as /bin/sh follow POSIX in this and/or do not allow the execution environment of a script to be messed up so strongly as through importing functions from the environment.
By the way, the script seems designed to be sourced, i.e. . ./mono-2.6-environment instead of ./mono-2.6-environment.
Had the same problem. Used brute force:
/bin/sh /full/path/to/configure --options
& this did the trick
(Of course I'd like to know why)
I encountered a similar error but in my case I forgot to add / before bin and I was encountering the bad interpreter error. Also tried to do
sudo apt-get install dos2unix -y package.
I was using this originally :
#! bin/bash ( i was missing / before bin )
Double check the path as well.
This could be a case of a shebang with homoglyphic unicode characters. In other words, you may have invisible or look-alike characters in the shebang which don't actually represent the string #!/bin/bash. Try looking at the characters in a hex editor.
what worked for me was when dos2Unix wasn't on the system I was working with:
sed -i s/{ctrl+v}{ctrl+m}// filename
This happens sometimes when file system goes funny.
Try to move or rename the file.
If you see "Stale file handle" error this is your problem.
e.g. happened us with CentOS docker
$ ./test.sh
-bash: ./test.sh: /bin/bash: bad interpreter: Invalid argument
$ ls -alstr test.sh
20 -r-xr-xr-x 0 omen omen 17874 Jun 20 01:36 test.sh
$ cp test.sh testcopy.sh
$ ./testcopy.sh
Happy Days
$ mv test.sh footest.sh
mv: cannot move ‘test.sh’ to ‘footest.sh’: Stale file handle
$ rm test.sh
rm: cannot remove ‘test.sh’: Stale file handle
You can copy the file and read it.
But not move it!
Nor remove it.
Some weird docker file-system thing maybe.
Solution: re-create the docker container OR maybe file system repair disk would help
OR of course format c: :-D :-o

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