$sth->stuff();
 #NOT return unless $timeleft;
 #if i'm here, I do not need to return, I can go on

##</code><code>##

local $SIG{ALRM}=sub { 
 return;  #IE, when ALRM strikes
# cut short execution of the routine and just return from
#there
};
alarm 10;#
$sth->stuff();
alarm 0;# if I'm here, I can safely continue

##</code><code>##

sub sth($$) {
$SIG{ALRM}=sub { 
 goto SUBEND;  #IE, when ALRM strikes
# cut short execution of the routine and just return from
#there
};
#....
#....
alarm 10;#
$sth->stuff();
alarm 0;# if I'm here, I can safely continue

SUBEND:
return;
}