SystemCallError is the base class for all low-level platform-dependent errors.

The errors available on the current platform are subclasses of SystemCallError and are defined in the Errno module.

File.open("does/not/exist")

raises the exception:

Errno::ENOENT: No such file or directory - does/not/exist

Return true if the receiver is a generic SystemCallError, or if the error numbers self and other are the same.

Return this SystemCallError's error number.

If errno corresponds to a known system error code, constructs the appropriate Errno class for that error, otherwise constructs a generic SystemCallError object. The error number is subsequently available via the errno method.