The most common three shells are
Your startup shell is specified by a program name as
the last field in your
/etc/passwd entry. For example,
csh in the
One confusing thing for MPE users is that some
commands, such as
printenv, are built into a
specific shell, while others such as
cp are just programs in the
Commands that are implemented as external programs
are the same in all shells, but require some extra system
overhead to create a separate process.
Built-in commands usually do not have their own
man pages, so you have to do
man ksh and read the description of the Korn shell.
For the benefit of MPE users who are new to UNIX we have created
a command cross-reference showing
the commands in each shell that correspond to each MPE command.