( ) - -, Linux . . , , , . , . . - , , , . , , , -, . .
, , .
:
KEY=value KEY="Some other value" KEY=value1:value2
:
- (). (UPPER CASE).
-
: -
=
:
- (Environmental Variables) - , . , .
- (Shell Variables) - , , . , , .
, env printenv. :
SHELL=/bin/bash TERM=xterm USER=demouser LS_COLORS=rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31;01:su=37;41:sg=30;43:ca:... MAIL=/var/mail/demouser PATH=/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games PWD=/home/demouser LANG=en_US.UTF-8 SHLVL=1 HOME=/home/demouser LOGNAME=demouser LESSOPEN=| /usr/bin/lesspipe %s LESSCLOSE=/usr/bin/lesspipe %s %s _=/usr/bin/printenv
env, printenv. . , printenv :
printenv SHELL
:
/bin/bash
?
set. set - , , , :
BASH=/bin/bash BASHOPTS=checkwinsize:cmdhist:expand_aliases:extglob:extquote:force_fignore:histappend:interactive_comments:login_shell:progcomp:promptvars:sourcepath BASH_ALIASES=() BASH_ARGC=() BASH_ARGV=() BASH_CMDS=() . . .
, less, :
set | less
echo:
echo $ BASH_VERSION
:
4.4.19 (1) -release
Linux
, .
- USER: ,
- EDITOR:
- HOME:
- PATH: , ,
- PS1: ( )
- PWD:
- _: ,
- MAIL:
- SHELL: , , (, bash, sh, zsh )
- LANG: ,
- DESKTOP_SESSION: , (GNOME, KDE)
- HISTFILESIZE: ,
- HISTSIZE: ,
- UID: UID
- HOSTNAME:
- TERM:
- OLDPWD:
- BASHOPTS: , bash.
- BASH_VERSION: bash, .
- BASH_VERSINFO: bash .
- COLUMNS: , .
- DIRSTACK: , pushd popd.
- IFS: . .
- SHELLOPTS: , set.
Linux
Linux , .
- export.
export VAR="value"
, .
NEW_VARIABLE "test", :
export NEW_VARIABLE='test'
:
printenv NEW_VARIABLE test
export, . , , .
Linux
, . : , .
.bashrc
- .bashrc.
.bashrc - , , . , GNOME screen , .bashrc.
, .bashrc:
export TZ="America/New_York"
source bashrc .
source ~/.bashrc
printenv , Linux, TZ.
$ printenv TZ America/New_York $ date Sat 19 Jan 2020 10:03:00 AM EDT
, !
.bash_profile
, login , .bash_profile.
$ export TZ="America/New_York" $ source ~/.bash_profile
etc/environment
, . Linux, /etc/environment.
, , , EDITOR .
$ export EDITOR="vi"
, , EDITOR .
, , , .
.bashrc:
echo "export VAR="value"" >> ~/.bashrc && source ~/.bashrc
.bash_profile:
echo "export VAR="value"" >> ~/.bash_profile && source ~/.bash_profile
/etc/environment:
echo "export VAR="value"" >> /etc/environment && source /etc/environment
Linux
, , , . Linux : unset .
unset
, unset :
unset <variable>
:
unset USERNAME printenv USERNAME <nothing>
set -n
, , set -n-n.
set -n USERNAME printenv USERNAME <nothing>
PATH Linux
Linux PATH, .
PATH, printenv:
printenv PATH /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
PATH, export .bashrc source:
echo "export PATH=":$PATH"" >> ~/.bashrc && source ~/.bashrc printenv PATH :/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
! PATH Linux.
, Linux : export, , .
, PATH.
