System command

set command

Display, set or remove environment variables in the current command session.

Availability: Microsoft Learn command reference spanning Windows client and Windows Server releases; some entries are legacy, role-specific, optional-feature or interactive subcommands.中文

Documented syntax

set
set context
set option
set verbose
set metadata

The linked Microsoft Learn article is the upstream authority. Availability may depend on Windows release, role, optional feature or interactive tool context.

Examples

Example usage for set.

set /a total=2+3

Parameters, options and clauses

Option / clause	Description
`<variable>=[<string>]`	Set a session variable; omitting the value clears it.
`/p <variable>=[<promptString>]`	Read a value from user input.
`/a <variable>=<expression>`	Evaluate an integer expression and store the result.
`Parameters`	Microsoft documents this argument or subcommand; check the linked reference for its required format and context.
`/?`	Display command help or the supported command-line usage.

Safety note

Review a command and its target before running it. Commands that alter files, services, accounts, disks, permissions or databases may be difficult to reverse. Test in a safe environment and keep backups.

Official reference ↗Back to directory