basic unix operations, basically a subset of the POSIX speci cation. Using this
unit should ensure portability across most unix systems.
errors
returns a string describing an operating system error code.
oldlinux
This unit is deprecated. This unit provides access to the linux operating system.
It provides most le and I/O handling routines that you may need. It implements most
of the standard C library constructs that you will nd on a Unix system. If you do a
lot of disk/ le operations, the use of this unit is recommended over the one you use
under Dos.
ports
This implements the various port[] constructs. These are provided for compatibility
only, and it is not recommended to use them extensively. Programs using this construct
must be run as ruit or setuid root, and are a serious security risk on your system.