Tootfinder

#define SIOCGIFINDEX 0x8933 /* name -> if_index mapping */
#define SIOGIFINDEX SIOCGIFINDEX /* misprint compatibility :-) */
-- /usr/include/bits/ioctls.h

Despite what you will read on the internet, exiting #Vim is really easy.
Just press the ESC key and then enter this simple line to exit the editor:
:let script=['#define _POSIX_SOURCE', '#include

#define BITCOUNT(x) (((BX_(x) (BX_(x)>>4)) & 0x0F0F0F0F) % 255)
#define BX_(x) ((x) - (((x)>>1)&0x77777777) \
- (((x)>>2)&0x33333333) \
- (((x)>>3)&0x11111111))
-- really weird C code to count the number of bits…