Signal

   

Declaration:

Function Signal (SigNum : Integer; Handler : SignalHandler) : SignalHandler;

Description:

Signal installs a new signal handler for signal SigNum. This call has the same functionality as the SigAction call.

The return value for Signal is the old signal handler, or nil on error.

Errors:

LinuxError is used to report errors :

SIG_ERR

An error occurred.

See also:

SigAction,Kill, Signal (2)

Example

Program example58;

{ Program to demonstrate the Signal function.}

{ 
do a kill -USR1 pid from another terminal to see what happens.
replace pid with the real pid of this program. 
You can get this pid by running 'ps'.
}

uses Linux;

Procedure DoSig(sig : Longint);cdecl;

begin
   writeln('Receiving signal: ',sig);
end; 

begin
   SigNal(SigUsr1,@DoSig);
   if LinuxError<>0 then
     begin
     writeln('Error: ',linuxerror,'.');
     halt(1);
     end;
   Writeln ('Send USR1 signal or press <ENTER> to exit'); 
   readln;
end.