new

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

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:

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. When $SAFE > 0 and the given tmpdir is tainted, it uses ‘/tmp’ as the temporary directory. Please note that ENV values are tainted by default, and Dir.tmpdir's return value might come from environment variables (e.g. $TMPDIR).

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.:

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

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

Exceptions

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