#Shebang for bash on mac how to#
#Shebang for bash on mac free#

HereвЂ™s a quick sample: #!/bin/bashДESTDIR=/media/diskid/user_backup/Documents/ That might not be a problem, but if you want to write longer scripts that reference paths often, you probably want to utilize variables. The above script is useful, but it has hard-coded paths. The other columns with a dash show that other users have no rights for that file at all. The first column of rights, rwx, shows that the owner of the file (jzb) has read, write, and e xecute permissions. To see the results, run ls -lh scriptname and youвЂ™ll see something like this: -rwx- 1 jzb jzb 21 03:08 echo To set it so that a script is executable by you and not the rest of the users on a system, use вЂњchmod 700 scriptnameвЂќ - this will let you read, write, and execute (run) the script - but only your user. You can do this using the chmod utility, which changes a fileвЂ™s mode. Save your file, and then make sure that itвЂ™s set executable. Rsync -avh -exclude='*.bak' /home/user/Documents/ /media/diskid/user_backup/Documents/

Just add the rsync command to the script that you want to use: #!/bin/bash LetвЂ™s say you want to run an rsyncВ command from the script, rather than typing it each time. Preface comments with the hash (#) character: #!/bin/bash WhatвЂ™s next? You might want to include a comment or two about what the script is for.

You could even omit that line if you wanted to run the script by sourcing it at the shell, but letвЂ™s save ourselves some trouble and add it to allow scripts to be run non-interactively. Confused? Scripts can be written for all kinds of interpreters - bash, tsch, zsh, or other shells, or for Perl, Python, and so on. This is used by the shell to decide which interpreter to run the rest of the script, and ignored by the shell that actually runs the script. The вЂњ#!вЂќ combo is called a shebangВ by most Unix geeks. Starting OffД®ach script starts with a вЂњshebangвЂќ and the path to the shell that you want the script to use, like so: #!/bin/bash Over time you can build on what you know and wind up doing more and more with scripts. Start small and use scripts to automate small tasks. All you need is a text editor and an idea of what you want to do.

#Shebang for bash on mac how to#

If you know how to run commands at the command line, you can learn to write simple scripts in just 10 minutes. That is, you can do some complicated things with shell scripts, but you can get there over time. If this is your first time writing a script, donвЂ™t worry - shell scripting is not that complicated. If youвЂ™ve ever wanted to learn how to write a shell script but didnвЂ™t know where to start, this is your lucky day. The first step is often the hardest, but donвЂ™t let that stop you.

#Shebang for bash on mac free#

For more great SysAdmin tips and techniques check out our free intro to Linux course. This is a classic article written by Joe вЂњZonkerвЂќ Brockmeier from the В archives.