The Bourne shell is an interactive command interpreter and command programming language.
The bsh command runs the Bourne shell.
The Bourne shell can be run either as a login shell or as a subshell under
the login shell. Only the login command can call the Bourne
shell as a login shell. It does this by using a special form of the bsh command
-bsh. When called with an initial hyphen (
the shell first reads and runs commands found in the system /etc/profile file
and your $HOME/.profile, if one exists. The /etc/profile file
sets variables needed by all users. Finally, the shell is ready to read commands
from your standard input.
If the File [Parameter]
parameter is specified when the Bourne shell is started, the shell runs the
script file identified by the File parameter, including
any parameters specified. The script file specified must have read permission;
setgid settings are ignored.
The shell then reads the commands. If either the -c or -s flag
is used, do not specify a script.