alert.pl

 alert(+Opts)

Display an alert at a specific time.

The predicate can send messages via Linux commands notify-send and zenity. There are 3 main elements in the message the title (Title) of the widow and the message (Mess) to which the time is prefixed.

Opts

critical(Crit=false)

escalate to critical level (Only relevant to notify messages. In some Oses it keeps the message on-screen till closed by user.)

debug(Dbg=false)

progress informational messages

help

print help and exit

help(Help=false)

print help and exit

message(Mess)

body of message

timeout(Tout=false)

time out in seconds. Default passes nothing, where notify expires according to defaults and zenity does not at all.

title(Title=title)

title of window/messsage

type(Type=both)

type of message: notify, zenity or both

when(At)

when (currently at('HH:MM'), at(HH,MM) and in(RelTime) are recognised)

RelTime can be of the form Xs, Ym or Zh which are interpreted as seconds minutes and hours. If there is no time specifier prostfix, then RelTime is interpreted in minutes.

According to some manual entries for the command, the implementation of notfiy-send is not stable for some parameters across OSes.

With a numerical Tout, the zenity call will expire as a failure, as interaction is expected. On Linux Mint 22.3, notify-send does not honour this flag, you can use Crit=true for a persistant message.

> upsh alert title=one message=two when=in=1 debug=true
% Sleeping for : 60 secs.

> which supsh
supsh: 	 aliased to upsh p !* >& /dev/null &

> upsh alert help
% upsh alert title=titlE message=messagE when=in=5s
% upsh alert title=titlE message=messagE when=at=9,0
%
% with supsh aliased to- supsh: 	 aliased to upsh p !* >& /dev/null &
% supsh alert title=titlE message=messagE when=at=16\\:00 type=notify

Different time formats.

> upsh alert title=titleE message=messagE when=in=0.2m debug=true
% Sleeping for : 12.0 secs.
% Title: titleE
% Msg: titleE
% Creating messages for both commands.
% Sending: notify-send(titleE,15:30
messagE)
% Sending: zenity(--info,--title,titleE,--text,15:30
messagE)

> upsh alert title=titleE message=messagE when=in=1s debug=true
% Sleeping for : 1 secs.
% Title: titleE
% Msg: titleE
...

upsh> date ; upsh p alert title=one message=two when=at=16,00 debug=true
Mon  9 Mar 15:32:06 GMT 2026
% Sleeping for : 1673.3508853912354 secs.
% Title: one
% Msg: two
...

Persistancy of messages.

> upsh alert title=one message=two when=in=1s critical=true type=notify
% in Linux Mint 22.3, this will create a persistant notify message

> upsh alert title=one message=two when=in=1s  timeout=4
% in Linux Mint 22.3, this will create a transient zenity message that will last 4s (def is persistent till user interaction)

author

- nicos angelopoulos

version

- 0:1 2021/04/09

- 0:2 2026/03/09, added option critical(Crit), postfix time and at(HH,MM) format (with examples)

To be done

- type check type