1$FreeBSD: src/bin/ed/README,v 1.7 1999/08/27 23:14:12 peter Exp $ 2$DragonFly: src/bin/ed/README,v 1.2 2003/06/17 04:22:49 dillon Exp $ 3 4ed is an 8-bit-clean, POSIX-compliant line editor. It should work with 5any regular expression package that conforms to the POSIX interface 6standard, such as GNU regex(3). 7 8If reliable signals are supported (e.g., POSIX sigaction(2)), it should 9compile with little trouble. Otherwise, the macros SPL1() and SPL0() 10should be redefined to disable interrupts. 11 12The following compiler directives are recognized: 13DES - to add encryption support (requires crypt(3)) 14NO_REALLOC_NULL - if realloc(3) does not accept a NULL pointer 15BACKWARDS - for backwards compatibility 16NEED_INSQUE - if insque(3) is missing 17 18The file `POSIX' describes extensions to and deviations from the POSIX 19standard. 20 21The ./test directory contains regression tests for ed. The README 22file in that directory explains how to run these. 23 24For a description of the ed algorithm, see Kernighan and Plauger's book 25"Software Tools in Pascal," Addison-Wesley, 1981. 26