Different Shells

HP-UX, like all UNIX variants, allows you to select among different shells. A lot of material is available on the POSIX shell, which is the default HP-UX shell in most cases. There is less information available on the other widely used shells, so I have decided to cover them in this chapter. The shell is important to you as a system administrator and user because it is your window into the system. I decided to include the KornShell and C shell in this chapter because so many new HP-UX users and system administrators use them as their shells even though the POSIX shell is the default on most systems. I included Bash because it is widely used in Open Source enviornments and many Open Source GNU tools are available for HP-UX 11i. The upcoming sections cover these three shells. The KornShell section also covers some important topics related to shells such as File Name Expansion, Redirection, Background Jobs , and umask and Permissions . Some of these topics have been covered in other chapters of the book, but these topics are closely related to your shell, so I decided to include them here as well.