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P4 CLI Documentation | 2026.1

# P4POPTIONS

Set P4 Proxy options for a Windows service.

## Usage notes

Used by Client? | Used by Server? | Command-Line Alternative | Can be set in P4CONFIG file?
--- | --- | --- | ---
No | Yes | `p4p %P4POPTIONS%` | N/A

## Value if not explicitly set

Operating System | Value
--- | ---
All | Null

## Notes

For example, if you normally run the Proxy with the command

    p4p -p 1999 -t mainserver:1666

you can set the `P4POPTIONS` variable for the Windows `proxysvc` to run with

    p4 set -S "Perforce Proxy" P4POPTIONS="-p 1999 -t mainserver:1666"

When you run P4P under the `"P4 Proxy"` service, the Proxy will listen to port 1999 and communicate with the Perforce service at `mainserver:1666`.

Most installations do not need to use `P4POPTIONS`, because there are already environment variables associated with most `p4p` options; in the example shown above, you can use `P4PORT` and `P4TARGET`. Use `P4POPTIONS` when you need to call `p4p` with options for which there are no corresponding environment variables, and when you are doing so within the context of a Windows service.

See P4 Proxy in the P4 Server Administration Documentation.

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