pierre@guepard:~/prog/asm$ nasm -f coff first.asm 
pierre@guepard:~/prog/asm$ gcc -o first first.o  driver.c lib/asm_io.o
first.o: file not recognized: File format not recognized
collect2: ld returned 1 exit status
pierre@guepard:~/prog/asm$ nasm -v
NASM version 0.99.05 compiled on Oct 22 2007