IT notes

exec

exec is a functionality of an operating system that runs an executable file in the context of an already existing process, replacing the previous executable. https://en.wikipedia.org/wiki/Exec_(system_call) exec replaces the current program in the current process, without forking a new process. Examples to use: exec csh This will just replace the existing shell with csh and only need to type exit once Within a script to startup python scripts, for example:

/bin/sh shell set

The Bourne shell (sh) is a shell, or command-line interpreter, for computer operating systems. The Bourne shell was the default shell for Unix Version 7. Most Unix-like systems continue to have /bin/sh—which will be the Bourne shell, or a symbolic link or hard link to a compatible shell even when other shells are used by most users. https://en.wikipedia.org/wiki/Bourne_shell set options In sh, the set built-in command has the following options: