How to force syswrite to write numbers? A number is a numerical value; I do not mean the squiggly lines we draw to represent numbers.

Perl keeps changing the values I try to write, in accordance with its 'does what you expect it to do' philosophy. Three days of official and unofficial documentation, I can't find a solution.

Some examples of Perl changing types behind my back: with this line: syswrite($SERIALPORT, $packet_out) 

$packet_out = 4;
On the serial wire: 0x34 (which is ASCII code for character 4)

$packet_out = '4';
On the serial wire: 0x34 (which is ASCII code for character 4)

$packet_out = 0x65;
On the serial wire: 0x31 0x30 0x31 (which, bizarrely, is ASCII code fo
+r '101' which is a string of the decimal ASCII code for 'e' which has
+ the ASCII code 0x65)

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When I say syswrite 4, I want a number 4 to go out the wire. This must be possible, and discussed already; anyone know how or where? I open the port like this: 
unless (open ($SERIALPORT, "+<", $comport)) {die "Cannot open $comport
+: $!"}
system("stty -cstopb hupcl ignbrk -iexten -echo -echoe -echok " . 
    "-echoctl -echoke -crtscts -ignpar cs8 9600 time 5 -icrnl " .
    "-ixon -opost -isig -icanon -F $comport");
die unless binmode($SERIALPORT, ':raw:bytes'); #numerous variations tr
+ied

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In reply to syswrite numbers, not strings by akujbida

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