How to make a permanent variable

Question

In terminal:

VAR="Extremely long and often used command"
echo $VAR

Output:

Extremely long and often used command

So far it works fine, but after restarting a terminal my variable doesn't exist. How to fix it?

The general rule is if it's a variable that is only useful to the shell, don't bother exporting it and just put it in .bashrc. If it's an environment variable put it in .profile, and you'll want to export it too. That should work. There's no way to know why it doesn't for you unless you provide more info (do you do anything weird with your rc files, etc.) — jw013, Nov 16 '12 at 16:04
Why on earth would one do anything weird with or in an rc file? I'm shocked that such things go on. — , Nov 16 '12 at 16:37
@BruceEdiger care to explain why you feel so strong about 'weird' things in an rc file? — jippie, Nov 16 '12 at 17:43
@0x6B6F77616C74 please explain what you want to use the variable for and why it is important that it survives a reboot. — jippie, Nov 16 '12 at 17:46
Regarding the new edit: see my first comment. Also, don't misuse variables: variables are not for storing full commands. Use a function or script instead. — jw013, Nov 16 '12 at 18:16
@jw013, can you please post that as an answer? Then we can take advantage of the stack exchange engine and propose edits, comment on your answer, etc. I think it's a decent one.... ;) — Wildcard, Mar 16 '16 at 00:53

score 9 · Accepted Answer · edited Feb 10 '18 at 20:49

9

You can put it in your .bash_profile, which gets executed every time you log in.

Or, if it is an alias for a long command, you can put this in your .bash_aliases file under your home directory:

alias short_version="very long command here"

edited Feb 10 '18 at 20:49

Jeff Schaller

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answered Nov 16 '12 at 18:25

MelBurslan

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If you have your aliases in .bash_aliases, you must source that file (with source or .) in .bashrc (or otherwise) for it to work - it's not done automatically, at least not for me. – Emanuel Berg Nov 16 '12 at 22:34
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@EmanuelBerg, some distros (notably Ubuntu) provide a default .bashrc that automatically sources .bash_aliases if it exists. But you're right, it's not a standard Bash startup file. – cjm Nov 19 '12 at 07:32
@cjm: Aha, so that's it. I've heard many people talk about that file so I suspected it was if not a standard, then at least a common practice, from somewhere. Ubuntu. – Emanuel Berg Nov 19 '12 at 20:00

score 2 · Answer 2 · answered Mar 09 '17 at 04:48

You can create/modify/delete permanent variables using kv-bash functions:

1) Download kv-bash file from github:

git clone https://github.com/damphat/kv-bash.git
cp -ar ./kv-bash/kv-bash /usr/local
chmod +x /usr/local/kv-bash

2) Import kv-bash functions:

# You can also put this line in .bash_profile
source kv-bash

3) Now create/modify variables

#let try create/modify/delete variable
kvset myEmail john@example.com
kvset myCommand "Very Long Long Long String"

#read the varible
kvget myEmail

#you can also use in another script with $(kvget myEmail)
echo $(kvget myEmail)

#delete variable
kvdel myEmail

I learned it from this https://hub.docker.com/r/cuongdd1/cloud-provisioning-packs/~/dockerfile/

Just letting people know there is a re-written fork of this with far more features. https://github.com/imyller/kv-sh Has dump, import, restore, exists and the ability for a local and fallback (ro) default database. — Shanness, Aug 16 '20 at 06:49

How to make a permanent variable

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