From Erlang Community

[edit] caveat

unless you really know what you're doing, you'll be better off using a linked-in driver or a port.

[edit] steps

1. run configure

2. add your bifs to erts/emulator/beam/bif.tab

bif re:grep/2 bif re:compile/1

3. create a C file

erts/emulator/beam/erl_bif_re.c

4. add your C file to erts/emulator/<arch>/Makefile

RUN_OBJS = $(OBJDIR)/erl_bif_re.o \

5. implement your bifs by stealing bits from existing erl_bif_*.c files

BIF_RETTYPE re_grep_2(BIF_ALIST_2){
  Eterm result;
  result = magic_function(); 
  BIF_RET(result);
}

6. run make; make install

[edit] notes

• steps 0-3 need only be done once.

• note that if you add

bif re:grep/2

to bif.tab there should be a erl_bif_re.c that implements

BIF_RETTYPE re_grep_2(BIF_ALIST_2);