What are the primary differences, pros and cons of NASM and FASM ?

• license - FASM is freeware with open source, NASM is GPL;
  
• speed - FASM is written in assembly, wheras NASM in C; also FASM is optimized, so it generates the output faster;
  
• syntax - is quite smilar, based on IDEAL mode of TASM; but there are some differences in assembler directives;
  
• preprocessor capabilities - FASM has an extended preprocessor (advanced macroinstructions); I don't know too much about NASM, but it's macro capabilities are extended too;
  
• support - FASM is updated very often, bugs disappear quickly, and new features are comming (although usually it is hard to convince Privalov to add new directives and features), and you have excellent support on this board; NASM has been dead for a long time, now as I know there is a team developing 64-bit version;
  

well, maybe this is biased to FASM, but generally these are the facts.

regards,
decard

More biased facts (However, I liked Nasm a lot until I discovered Fasm)

Fasm is a multipass assembler, Nasm performs only two passes
Fasm runs on MenuetOS (and is easier to port to other systems).
Fasm is smaller in size and in source length and is well written permitting better maintainability/extendibility.
IMHO the preprocessor directives are cleaner and hus permit writing code easier to read.

fasm is maintained by privalov, and he is always ready to explain you why is some behavior of fasm used (i bet he explains every change / addition zound stimes again and again), he can aid you if you are going to learn from / modify it's sources etc. In my opinion he is another pro of FASM.

A key reason that NASM is still widely used is that it supports more output formats than FASM does. The support for including debugging information is nice too.

Also a minor correction: NASM is LGPL, not GPL, so it's a little more free. Both NASM and FASM are open source.

As far as portability, I've had better luck getting NASM to run on other OSes than I've had with FASM. That's largely due to the use of standard C libraries though.

Another key reason that Nasm is still widely used is that Nasm goes in (near) all Linux distros as developement tool.
Fasm is still unknown to the mainstream, but I am confident that this will change soon.

Good point.

What are the supported export file formats for FASM?I mean for Emu8086 they are:EXE,BOOT,COM,and BIN.
For FASM?

Look at manual:
pure asm (COM etc.), MZ, PE (EXE, DLL), COFF, ELF (System V, but with brandelf you can simply change it into Linux. With FreeBSD I'm still trying to use, but in 5.x there is prolem with sys_brk in Linux compatibity mode ).

I wonder if it is legal to say, that BOOT=COM=BIN cuz they all are binary in the way they are executed or did BOOT have headers ^o) ...
...hmm, you can change your .bin to .com and you have a program:D vóila:P

I think BOOT has header.The only pure thing i think is BIN,Correct me if im wrong!

You aren't only

What are the primary differences, pros and cons of TASM and FASM ? =P

Tasm: Con--It costs money.

Fasm: Pro--It's free.

nuff said.

Tasm: micro$ofty intel syntax (copied from MASM)
Fasm: own, simplified (and better, M$ free) intel syntax.

actually Fasm doesn't have "its own" syntax: as Privalov said, it is based on the IDEAL mode of TASM, thus you can make TASM use similar syntax. Notice that NASM and GoASM use this syntax too

Let's just say, that it's not AT&T syntax (which is imo "just different" - or in other words "IMO quer, and makes eyes bleed" )

Embrance: BOOT does *not* have a header. It has a different origin in memory than a totally flat binary though.

Ok.Thamnks for defination!

i still didn't comprehend this - is NASM project alive?