We use the ftruncate function in PHP to truncate a file to a given length.
{{code:php $f = fopen('/path/to/foobar', 'w') ftruncate($f, 10); fclose($f); }}
The same task can be accomplished in Ruby with the File#truncate method:
{{code:ruby File.open('/path/to/foobar', 'w') do |f| f.truncate(10) end }}
Ruby also provides the File.truncate class method for convenience. It allows
you to truncate a file without opening it yourself.
{{code:ruby File.truncate('/path/to/foobar', 10) }}
{{related:
filesystem/fopen
filesystem/fseek
}}