doctest.StringIO.readline

StringIO.readline(length=None)[source]

Read one entire line from the file.

A trailing newline character is kept in the string (but may be absent when a file ends with an incomplete line). If the size argument is present and non-negative, it is a maximum byte count (including the trailing newline) and an incomplete line may be returned.

An empty string is returned only when EOF is encountered immediately.

Note: Unlike stdio’s fgets(), the returned string contains null characters (‘0’) if they occurred in the input.