41 lines
1.2 KiB
Markdown
41 lines
1.2 KiB
Markdown
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# The `env` command
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The `env` command in Linux/Unix is used to either print a list of the current environment variables or to run a program in a custom environment without changing the current one.
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## Syntax
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```bash
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env [OPTION]... [-] [NAME=VALUE]... [COMMAND [ARG]...]
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```
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## Usage
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1. Print out the set of current environment variables
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```bash
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env
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```
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2. Run a command with an empty environment
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```bash
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env -i command_name
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```
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3. Remove variable from the environment
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```bash
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env -u variable_name
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```
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4. End each output with NULL
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```bash
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env -0
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```
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## Full List of Options
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|**Short Flag** |**Long Flag** |**Description** |
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|:---|:---|:---|
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|`-i`|`--ignore-environment`|Start with an empty environment|
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|`-0`|`--null`|End each output line with NUL, not newline|
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|`-u`|`--unset=NAME `|Remove variable from the environment|
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|`-C`|`--chdir=DIR`|Change working directory to DIR|
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|`-S`|`--split-string=S`|Process and split S into separate arguments. It's used to pass multiple arguments on shebang lines|
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|`-v`|`--debug`|Print verbose information for each processing step|
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|-|`--help`|Print a help message|
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|-|`--version`|Print the version information|
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