INTRO(1V)

NAME
intro - introduction to System V compatibility commands

DESCRIPTION

Various commands are provided in the directory /usr/5bin to offer compatibility with widely used System V commands. These commands are intended to be reasonably conformant with the X/Open Portability Guide Issue 3. For information about how to use such commands in a portable fashion this guide should be consulted, rather than these manual pages, as the manual pages describe some facilities which are not included in the X/Open specification.

In many cases if a command exists in /usr/5bin a command with a similar name but different semantics will exist elsewhere in the system - probably /usr/bin or /usr/ucb. If this is so the other command will be documented in the appropriate manual page, normally command(1).

The order of directories in the shell PATH environment variable controls which environment a user of that shell will see. Two orders are possible:

...:/usr/5bin:/usr/bin:/usr/ucb:...
    This ordering gives a System V (X/Open) environment. BSD commands may also be available, but where a conflict in command semantics exists the X/Open specificaton will be followed. The man(1) program will locate (1V) pages in preference to (1) ones.

...:/usr/ucb:/usr/bin:/usr/5bin:...
    This ordering gives a BSD environment. System V commands may also be available, where their name does not clash with a BSD command. The man(1) program will locate section (1) manual pages in preference to those from section (1V).

Other orderings of these three directories are possible, but will give unpredictable semantics. The contents of the directory /usr/bin do not consist solely of commands with consistent semantics.