---
name: umask
status: documented
runtime: pp
source: src/runtime/pp/filemod.rs
---
```{index} single: umask; Perl built-in (pp runtime)
```

# umask

## Synopsis

```perl
my $old_mask = umask(0022);  # Set new mask, return old
my $current  = umask();      # Query current mask
```

## Description

Gets or sets the process file-creation permission mask.

With an argument, sets the umask to the given value and returns the
previous mask.  Without an argument (or with undef), queries the
current mask by temporarily setting it to 0 and restoring it, then
returns the value.

The umask affects the default permissions of newly created files
and directories.  The actual permissions are `requested & ~umask`.

Returns the previous umask as an integer (typically displayed in
octal).

## See also

chmod, mkdir, open