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Questions tagged [shell-script]

A shell script is a script written for the shell, or command line interpreter, of an operating system.

It is often considered a simple domain-specific programming language. Typical operations performed by shell scripts include file manipulation, program execution, and printing text.

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Batch converting PNG to JPG in linux

Does anyone know a good way to batch-convert a bunch of PNGs into JPGs in linux? (I'm using Ubuntu). A png2jpg binary that I could just drop into a shell script would be ideal.
nedned
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looping through `ls` results in bash shell script

Does any one have a template shell script for doing something with ls for a list of directory names and looping through each one and doing something? I'm planning to do ls -1d */ to get the list of directory names.
Daniel A. White
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What does export do in BASH?

Possible Duplicate: Difference between “a=b” and “export a=b” in bash It is hard to admit, but I have never really understood what exactly export does to an environment variable. I know that if I don't export a variable I sometimes can't see it…
Chas. Owens
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Check if any of the parameters to a bash script match a string

I'm trying to write a script where I want to check if any of the parameters passed to a bash script match a string. The way I have it setup right now is if [ "$3" != "-disCopperBld" -a "$4" != "-disCopperBld" -a "$5" != "-disCopperBld" -a "$6" !=…
iman453
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When must I use #!/bin/bash and when #!/bin/sh?

When is #!/bin/bash more appropriate than #!/bin/sh in a shell script?
Hendré
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How to execute .sh file on Windows?

When I am trying to execute a file(name.sh) in the command line by the command ./name.sh , I am getting the error that: "." is not recognized as an internal or external command, operable or batch file please help me execute the .sh file
sushant
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11 answers

Log rotation of stdout?

I have a Linux program which can write information to stdout and stderr. I have a shell script which redirects that output to a file in /var/log. (Via >> and 2>&1.) Is there a way to make that log file rotate? (max size, then switch to a different…
Miral
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Avoid unwanted path in Zip file

I'm making a shell script to package some files. I'm zipping a directory like this: zip -r /Users/me/development/something/out.zip /Users/me/development/something/folder/ The problem is that the resultant out.zip archive has the entire file path in…
jerwood
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Determine the architecture of a Mac from the command line or script?

I'm writing a shell script, and I need to know the architecture, i.e. PPC or Intel. Back in the day, there was a program /bin/arch that told you, but my Mac doesn't seem to have it. Is there an easy way I can do this? Grep for something in a…
Brian Postow
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What is the difference between set, env, declare and export when setting a variable in a Linux shell?

What is the difference between set, env, declare and export when setting a variable in a Linux shell, such as bash?
user3872279
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How to POST file contents using cURL?

I want to do an HTTP POST of the contents (as a string) of a local file located at path/to/my-file.txt to a URL endpoint at http://example.com/. For example, I might want to do the following: Extract the contents of the file my-file.txt as a…
Mowzer
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How can I compare a variable to a text string, rather than integer, in an if/else statement?

In the process of writing a shell script, I ran into an issue with the following if/else statement that falls somewhere in the middle of the script: if [ $act -eq "add" ] then read - "add or update: " $comm git commit -m "$comm $file" else …
tony_perkis666
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How to extract a complete list of extension types within a directory?

Within a directory, and recursively within it's sub-directories, meaning every directory within a directory is processed, how do I compile a complete list of unique extensions within the directory? OS is Windows XP with all the current updates, but…
blunders
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What is wrong with “echo $(stuff)” or “echo `stuff`”?

I used one of the following echo $(stuff) echo `stuff` (where stuff is e.g. pwd or date or something more complicated). Then I was told this syntax is wrong, bad practice, non-elegant, excessive, redundant, overly complicated, cargo cult…
Kamil Maciorowski
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Populating Array in DOS Batch Script

How can I setup an array variable in a DOS batch script? I would like to load it with a list of file names to process. I really would like to keep this as simple as possible. Thank you.
Jim Fell
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