Type:
Class
Raised when an IO operation fails.
File.open("/etc/hosts") {|f| f << "example"}
#=> IOError: not opened for writing
File.open("/etc/hosts") {|f| f.close; f.read }
#=> IOError: closed stream
Note that some IO failures raise +SystemCallError+s and these are not subclasses of IOError:
File.open("does/not/exist")
#=> Errno::ENOENT: No such file or directory - does/not/exist