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class method

Tempfile.new

new(basename="", tmpdir=nil, mode: 0, **options)

Creates a temporary file with permissions 0600 (= only readable and writable by the owner) and opens it with mode “w+”.

It is recommended to use Tempfile.create { … } instead when possible, because that method avoids the cost of delegation and does not rely on a finalizer to close and unlink the file, which is unreliable.

The basename parameter is used to determine the name of the temporary file. You can either pass a String or an Array with 2 String elements. In the former form, the temporary file’s base name will begin with the given string. In the latter form, the temporary file’s base name will begin with the array’s first element, and end with the second element. For example:

Example
file = Tempfile.new('hello')
file.path  # => something like: "/tmp/hello2843-8392-92849382--0"

# Use the Array form to enforce an extension in the filename:
file = Tempfile.new(['hello', '.jpg'])
file.path  # => something like: "/tmp/hello2843-8392-92849382--0.jpg"

The temporary file will be placed in the directory as specified by the tmpdir parameter. By default, this is Dir.tmpdir.

Example
file = Tempfile.new('hello', '/home/aisaka')
file.path  # => something like: "/home/aisaka/hello2843-8392-92849382--0"

You can also pass an options hash. Under the hood, Tempfile creates the temporary file using File.open. These options will be passed to File.open. This is mostly useful for specifying encoding options, e.g.:

Example
Tempfile.new('hello', '/home/aisaka', encoding: 'ascii-8bit')

# You can also omit the 'tmpdir' parameter:
Tempfile.new('hello', encoding: 'ascii-8bit')

Note: mode keyword argument, as accepted by Tempfile, can only be numeric, combination of the modes defined in File::Constants.

Exceptions

If Tempfile.new cannot find a unique filename within a limited number of tries, then it will raise an exception.

See also .create .open #close also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.0