I have been trying for an hour to pack a simple number into a type 'S'
I have a small number < 10 and need to smash it into a unit16. 

I think the Perl "pack()" should take a number < 64k and PACK it into
16 contiguous bits resembling a uint16_t in C. All 5000 attempts to 
figure out this simple function have failed. What am I doing wrong?

In C:
unit16_t count;  // Tiny, 1 digit integer
uint48_t rgb;    // Full 48 binary bits from 3, uint16s, r, g and b
uint64_t rgbc;   // The final data, just like RGBA

memcpy(rgbc+0, rgb,   3*sizeof(uint16_t));
memcpy(rgbc+3, count, 1*sizeof(uint16_t));

// Voila! 4 ushort numbers in a row in RGBC "PACKED" into 64 adjoining
+ bits

Conceptually this is what I want to do:
Take 6 bytes of RGB and 2 bytes of count into a PACK them into a 'Q' 6
+4 
$rgbc = pack('Q', $rgb, $count);
"Pack a quad from 2 variables and store in RGBC"

I have a test number, 0x4567 = decimal 17757
I have a 48 bit RGB dragged from a binary .RAW file in a hash key
The tiny count is the data value for an RGB key.

I want to write an RGBC file with the count appended to the end of the
+ 
RGB value so I will  have 4, unit16_t values to make a uint64_t RGBC

How does one "Pack" a small number into a 16 bit unsigned integer??
------------------------------

Attempts:

Perl:
http://perldoc.perl.org/functions/pack.html
pack TEMPLATE,LIST
The TEMPLATE is a sequence of characters that give the order and type 
+of 
values, as follows:
        S  An unsigned short value.

    $count=17767;  # C=0x4567=Dec17757
    $c16 = pack("S", $count);  # Pack COUNT to 
    @c = pack("S*", $count);  # == 0000
    printf("Count= dec %d, hex 0x%04hx, c16=0x%04hx, \@c[%d]=%s\n", 
        $count, $count, $c16, scalar @c, join(", ", @c));
    printf("c[0]=%d=0x%08x, c[1]=%d=0x%08x\n", $c[0], $c[0],$c[1],$c[1
+]);
->
Count= dec 17767, hex 0x4567, c16=0x0000, @c[1]=gE
c[0]=0=0x00000000, c[1]=0=0x00000000
and many error/warning messages

Unpack?

Count= dec 17767, hex 0x4567, c16=0x0000, @c[2]=14129, 13879
c[0]=14129=0x00003731, c[1]=13879=0x00003637

17767 dec = 0b100010101100111
14129 dec = 0b11011100110001   <<< totally random?
13879 dec = 0b11011000110111     

The number packs into a single 'S'  with a value of 0x0000
But, it also packs into an array of unsigned shorts with weird
values c[0]=14129=0x3731, c[1]=13879=0x3637
None of these integers or hex values bears any resemblance to my numbe
+r
------------------------------------------

Obviously the wrong approach:
Try putting the number in as a text literal, "17757":
    @c = unpack("S*", "17757");  # == 0000
    printf("\@c[%d]=%s\n", scalar @c, join(", ", @c));
    printf("c[0]=%d=0x%08x, c[1]=%d=0x%08x\n", $c[0], $c[0],$c[1],$c[1
+]);

@c[2]=14129, 13623
c[0]=14129=0x00003731, c[1]=13623=0x00003537
Same 

--------------------------------------

Try using hex, 0x4567
    @c = pack("S*", 0x4567);  # == 0000
    printf("\@c[%d]=%s\n", scalar @c, join(", ", @c));
    printf("c[0]=%d=0x%08x, c[1]=%d=0x%08x\n", $c[0], $c[0],$c[1],$c[1
+]);
    return();

@c[1]=gE              One array value "gE"
c[0]=0=0x00000000    Prints as 0

--------------------------------------

Try doing some math on it so it knows its a number
    @c = pack("S*", $c16=17757*1);  # == 0000
    printf("\@c[%d]=%s\n", scalar @c, join(", ", @c));
    printf("c[0]=%d=0x%08x, c[1]=%d=0x%08x\n", $c[0], $c[0], $c[1], $c
+[1]);
    return();

@c[1]=]E             Weird text and zero for decimal and hex
c[0]=0=0x00000000

------------------------------------------

Confusing pack with unpack? I just used unpack to read a binary RAW fi
+le.
It worked exactly as expected. 
    @c = unpack("S*", "17757");  # == 0000
    printf("\@c[%d]=%s\n", scalar @c, join(", ", @c));
    printf("c[0]=%d=0x%08x, c[1]=%d=0x%08x\n", $c[0], $c[0], $c[1], $c
+[1]);
@c[2]=14129, 13623
c[0]=14129=0x00003731, c[1]=13623=0x00003537

----------------------------------------------

@c = pack("S*", "17757");  # == 0000
    printf("\@c[%d]=%s\n", scalar @c, join(", ", @c));
    printf("c[0]=%d=0x%08x, c[1]=%d=0x%08x\n", $c[0], $c[0], $c[1], $c
+[1]);

@c[1]=]E
Argument "]E" isn't numeric in printf at C:\bin\bb.pl line 347.
Use of uninitialized value in printf at C:\bin\bb.pl line 347.
Use of uninitialized value in printf at C:\bin\bb.pl line 347.
c[0]=0=0x00000000, c[1]=0=0x00000000


====================================================
====================================================

    open(IN, "<$file")  or die("CCS: ERROR! <Opening '$file': $!\n");
    for($ii = 0; $ii < $sr_num; $ii++)  {
        $sr_len = sysread(IN, $buf, $bsize);  # SysRead Length
        $tr_len += $sr_len;  # Total Read Length
        $tr_num++;           # Total Read Number 
        while($buf)  {
            $rgb=substr($buf, 0, 6, '');  # Nibble 6 bytes 
            $rgb2c{$rgb}++;  
        }
    }  # End For II loop
        
    foreach $rgb (keys %rgb2c)  {
        $count = $rgb2c{$rgb};
        # Attempt to take known 6 byte RGB, some psychotic 
        # perl number and smash them together into a QUAD
        # a uint64 RGBC value just like a standard RGBA
        $rgbc = pack('Q', $rgb, $count);
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