---
name: "Perl::Critic::Policy::Community::OpenArgs"
section: "3pm"
platform: "linux"
package: "libperl-critic-community-perl"
version: "1.0.4-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Perl::Critic::Policy::Community::OpenArgs"
---

# Perl::Critic::Policy::Community::OpenArgs(3pm)

Always use the three-argument form of open

## NAME

Perl::Critic::Policy::Community::OpenArgs - Always use the three-argument form of open

## DESCRIPTION

The `open()` function may be called in a two-argument form where the filename is parsed to determine the mode of opening, which may include piping input or output. (In the one-argument form, this filename is retrieved from a global variable, but the same magic is used.) This can lead to vulnerabilities if the filename is retrieved from user input or could begin or end with a special character. The three-argument form specifies the open mode as the second argument, so it is always distinct from the filename.

```
  open FILE;                   # not ok
  open my $fh, "<$filename";   # not ok
  open my $fh, '<', $filename; # ok
```

This policy is similar to the core policy Perl::Critic::Policy::InputOutput::ProhibitTwoArgOpen, but additionally prohibits one-argument opens.

## AFFILIATION

This policy is part of Perl::Critic::Community.

## CONFIGURATION

This policy is not configurable except for the standard options.

## AUTHOR

Dan Book, `"dbook@cpan.org"`

## COPYRIGHT AND LICENSE

Copyright 2015, Dan Book.

This library is free software; you may redistribute it and/or modify it under the terms of the Artistic License version 2.0.

## SEE ALSO

Perl::Critic