The main work of the pack1D routine is in the for loop near the bottom. It takes an array of numbers and puts them into a string using a fixed size.

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|int|int|int|
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You can then unpack it with because you know the size of each element in the string.

#pack
work = sv_2mortal(newSVpv("", 0));
for (i=0; i<=n; i++) {
  work2 = av_fetch( array, i, 0 ); /* Fetch */
  if (work2==NULL)
    nval = 0.0;   /* Undefined *
  else {
    if (SvROK(*work2))
      goto errexit;     /*  Croak if reference [i.e. not 1D] */
      nval = SvNV(*work2);
  }
  iscalar = (int) nval;
  sv_catpvn( work, (char *) &iscalar, sizeof(int));
}
#unpack
for (i=0; i<m; i++) {
    av_store( array, i, newSViv( (IV)ivar[i] ) );
}
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