What is Shell?
The UNIX shell program interprets user commands which are either directly entered by the user, or which can be read from a file called the shell script or shell program. Shell scripts are interpreted, not compiled. The shell reads commands from the script line per line and searches for those commands on the system.
The below command is used to check known shells in a UNIX system.
root@localhost$ cat /etc/shells # List of acceptable shells for chpass(1). # Ftpd will not allow users to connect who are not using # one of these shells. /bin/bash /bin/csh /bin/dash /bin/ksh /bin/sh /bin/tcsh /bin/zsh
To change the shell, just write down the shell name; since a shell is an executable file (program), the current shell activates it and it gets executed. A new prompt is usually shown because each shell has its typical appearance.
Continue reading “Debugging in Shell Script”