Bash 5 reference · Shell Builtins and Syntax

export (Bash builtin)

Mark variables so child processes inherit them; one-off variables can also be set for a single command.

Bash 5

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Syntax

export NAME[=VALUE]...   NAME=VALUE command

Parameter	Description
`-n`	Remove the export attribute.
`-p`	List exported variables.

Plain versus exported

token=abc
bash -c 'echo "child: [${token:-}]"'
export token
bash -c 'echo "child: [$token]"'

Output

child: []
child: [abc]

Run this on your computer — see “Get Started” for setup.

A variable for one command

LOG_LEVEL=debug bash -c 'echo "$LOG_LEVEL"'
echo "afterwards: [${LOG_LEVEL:-unset}]"

Output

debug
afterwards: [unset]

Run this on your computer — see “Get Started” for setup.

source · Run a file's commands in the current shell, so its variables and functions stay defined; . is the POSIX spelling.
declare · Declare variables with attributes: arrays, associative arrays, integers, read-only values and exported variables.
Bash Environment Variables and PATH · tutorial