Linux Assembly Printing Numbers

[c++noobie]

I'm running Arch Linux on an x86_64 system with a patched 2.6.33 kernel for bootsplashing, shouldn't affect what I'm doing. I'm trying to print out a number to the screen. I'm fairly new to assembly, and I don't really know my way around convention or other things to make it easier, so if there's a better way to do any of this stuff, please let me know. Anyway, my function produces a string as expected on the stack. Analyzing with gdb at the time right before the system call, %rdx is the correct length and %rcx is a null terminated string ending with \n containing the number, but the system call doesn't print it. I don't know what I'm doing wrong. If you could, please help me out. Thank you very much. Here's the code:

.section .data

  .globl main
    .type main,@function

.section .text
main:
  pushq %rbp
  movq  %rsp,%rbp
  subq  $40,%rsp       #40 bytes allocated locally

  movq  %rsp,%rax      #set rax to the local variables
main_while:            #while loop, zero that local allocation
  cmpq  %rax,%rbp      #exit when you get back to the base pointer
  jge   main_while_end
  andq  $0,(%rax)
  addq  $4,%rax
  jmp   main_while
main_while_end:

  std                  #set to decrement to put the number into the string backward
  movq  %rbp,%rdi

  movq  $10,%rax       #put a new line
  stosb

  movq  $13753,%rax    #the number we're printing out
  movq  $10,%rcx       #ten in %rcx for division purposes
main_do:
  cdq 
  idivq %rcx
  orb   $0x30,%dl      #add 0x30, 0x30 + n is the ascii code for n if n < 10
  movq  %rax,%rbx      #save %rax / 10 in %rbx
  movq  %rdx,%rax      #move %rax % 10 to %rax for printing
  stosb
  movq  %rbx,%rax      #put %rax / 10 back
  cmpq  $0,%rax
  jne   main_do

  incq  %rdi           #back up one to where the string begins and save it on the stack
  pushq %rdi

  cld                  #set to increment for counting the length

#find string length by setting all %rcx bits, using scasb to scan
#scanning for '\0' then reversing %rcx after the scan and decrement
  xorq  %rcx,%rcx      #set all rcx bits
  notq  %rcx

  subb  %al,%al        #searching for NULL

  repne scasb          #start the scan

  notq  %rcx           #reverse bits and subtract one
  decq  %rcx

  movq  %rcx,%rdx      #length in %rdx
  popq  %rcx           #pop saved string location to %rcx
  movq  $1,%rbx        #file handle in %rbx, 1 == stdout
  movq  $4,%rax        #system call in %rax, 4 == write
  int   $0x80          #call the kernel

  movq  $0,%rbx        #exit status in %rbx
  movq  $1,%rax        #system call in %rax, 1 == exit
  int   $0x80          #call the kernel

.end