xref: /freebsd/bin/ed/README (revision 41059135ce931c0f1014a999ffabc6bc470ce856)
1$FreeBSD$
2
3ed is an 8-bit-clean, POSIX-compliant line editor.  It should work with
4any regular expression package that conforms to the POSIX interface
5standard, such as GNU regex(3).
6
7If reliable signals are supported (e.g., POSIX sigaction(2)), it should
8compile with little trouble.  Otherwise, the macros SPL1() and SPL0()
9should be redefined to disable interrupts.
10
11The following compiler directives are recognized:
12DES		- to add encryption support (requires crypt(3))
13NO_REALLOC_NULL	- if realloc(3) does not accept a NULL pointer
14BACKWARDS	- for backwards compatibility
15NEED_INSQUE	- if insque(3) is missing
16
17The file `POSIX' describes extensions to and deviations from the POSIX
18standard.
19
20The ./test directory contains regression tests for ed. The README
21file in that directory explains how to run these.
22
23For a description of the ed algorithm, see Kernighan and Plauger's book
24"Software Tools in Pascal," Addison-Wesley, 1981.
25