mjhjmtu

I wrote simple script which is running all the time and whenever the size of a file is changed it will write something like "The size has changed" to terminal but instead of terminal message, is it possible to actually get some prompt or some alert sound like in C?

In C you can output the BEL character 'a'. In a script you can do so with:

echo -e 'a'

If you don't get a sound with that, be sure to check that there is no

blacklist pcspkr

in your /etc/modprobe.d/blacklist.conf (and if there is comment it out and reboot).

Alternatively, if you have a nice sound short sound file xyz.mp3, and have vlc installed, you can do:

cvlc --no-one-instance --volume 100 --quiet --no-loop --no-repeat --play-and-exit xyz.mp3

If your terminal does not make any sound, it still (more likely than not) can make a visible alarm:

tput flash

For most systems, tput accepts terminfo names including flash. The terminfo manual for ncurses says:

 flash_screen flash vb visible bell (may
 not move cursor)

and

 If the terminal has a way of flashing the screen to indi-
 cate an error quietly (a bell replacement) then this can
 be given as flash; it must not move the cursor.

A few implementations accept only termcap names. Some terminal emulators do not flash the screen using any method (and in ncurses' terminal database, the preferred terminal description for those excludes the feature). Some of those may set TERM to xterm (but xterm itself works).

how to get service start & stop alert through script