not_a_bijection

5 ms·

1. 1.▲
   by not_a_bijection 3mo ago

   I think fork() is more of a PDP-7 mistake than a PDP-11 mistake. On the original UNIX system, memory was so limited that the only sane partitioning was to write the running program's memory image to disk, then reuse the running image a
2. 2.▲
   by not_a_bijection 4mo ago

   Not in C, unless at least one of the pointers were marked `restrict`.
3. 3.▲
   by not_a_bijection 5mo ago

   That's even more useful because of x86's braindamanged "setcc", which only affects the lowest byte of the destination, AFAIR, and so always has to be combined with a zeroing idiom before the setcc or a zero extension aft
4. 4.▲
   by not_a_bijection 5mo ago

   You can do better. X86 has both "op [mem], reg" and "op reg, [mem]" variants of most instructions, where "[mem]" can be a register too. So you have two ways to encode "xor eax, eax", differing by whic