General-purpose x86 assembler

 Netwide Assembler. NASM will currently output flat-form binary files,
 a.out, COFF and ELF Unix object files, and Microsoft 16-bit DOS and
 Win32 object files.
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 Also included is NDISASM, a prototype x86 binary-file disassembler
 which uses the same instruction table as NASM.
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 NASM is released under the GNU Lesser General Public License (LGPL).