2
3This version of ed(1) is not strictly POSIX compliant, as described in
4the POSIX 1003.2 document. The following is a summary of the omissions,
5extensions and possible deviations from POSIX 1003.2.
6
7OMISSIONS
8---------
91) For backwards compatibility, the POSIX rule that says a range of
10 addresses cannot be used where only a single address is expected has
11 been relaxed.
12
132) To support the BSD `s' command (see extension [1] below),
14 substitution patterns cannot be delimited by numbers or the characters
15 `r', `g' and `p'. In contrast, POSIX specifies any character expect
16 space or newline can used as a delimiter.
17
18EXTENSIONS
19----------
201) BSD commands have been implemented wherever they do not conflict with
21 the POSIX standard. The BSD-ism's included are:
22 i) `s' (i.e., s[n][rgp]*) to repeat a previous substitution,
23 ii) `W' for appending text to an existing file,
24 iii) `wq' for exiting after a write,
25 iv) `z' for scrolling through the buffer, and
26 v) BSD line addressing syntax (i.e., `^' and `%') is recognized.
27
282) If crypt(3) is available, files can be read and written using DES
29 encryption. The `x' command prompts the user to enter a key used for
30 encrypting/ decrypting subsequent reads and writes. If only a newline
31 is entered as the key, then encryption is disabled. Otherwise, a key
32 is read in the same manner as a password entry. The key remains in
33 effect until encryption is disabled. For more information on the
34 encryption algorithm, see the bdes(1) man page. Encryption/decryption
35 should be fully compatible with SunOS des(1).
36
373) The POSIX interactive global commands `G' and `V' are extended to
38 support multiple commands, including `a', `i' and `c'. The command
39 format is the same as for the global commands `g' and `v', i.e., one
40 command per line with each line, except for the last, ending in a
41 backslash (\).
42
434) An extension to the POSIX file commands `E', `e', `r', `W' and `w' is
44 that <file> arguments are processed for backslash escapes, i.e., any
45 character preceded by a backslash is interpreted literally. If the
46 first unescaped character of a <file> argument is a bang (!), then the
47 rest of the line is interpreted as a shell command, and no escape
48 processing is performed by ed.
49
505) For SunOS ed(1) compatibility, ed runs in restricted mode if invoked
51 as red. This limits editing of files in the local directory only and
52 prohibits shell commands.
53
54DEVIATIONS
55----------
561) Though ed is not a stream editor, it can be used to edit binary files.
57 To assist in binary editing, when a file containing at least one ASCII
58 NUL character is written, a newline is not appended if it did not
59 already contain one upon reading. In particular, reading /dev/null
60 prior to writing prevents appending a newline to a binary file.
61
62 For example, to create a file with ed containing a single NUL character:
63 $ ed file
64 a
65 ^@
66 .
67 r /dev/null
68 wq
69
70 Similarly, to remove a newline from the end of binary `file':
71 $ ed file
72 r /dev/null
73 wq
74
752) Since the behavior of `u' (undo) within a `g' (global) command list is
76 not specified by POSIX, it follows the behavior of the SunOS ed:
77 undo forces a global command list to be executed only once, rather than
| 2
3This version of ed(1) is not strictly POSIX compliant, as described in
4the POSIX 1003.2 document. The following is a summary of the omissions,
5extensions and possible deviations from POSIX 1003.2.
6
7OMISSIONS
8---------
91) For backwards compatibility, the POSIX rule that says a range of
10 addresses cannot be used where only a single address is expected has
11 been relaxed.
12
132) To support the BSD `s' command (see extension [1] below),
14 substitution patterns cannot be delimited by numbers or the characters
15 `r', `g' and `p'. In contrast, POSIX specifies any character expect
16 space or newline can used as a delimiter.
17
18EXTENSIONS
19----------
201) BSD commands have been implemented wherever they do not conflict with
21 the POSIX standard. The BSD-ism's included are:
22 i) `s' (i.e., s[n][rgp]*) to repeat a previous substitution,
23 ii) `W' for appending text to an existing file,
24 iii) `wq' for exiting after a write,
25 iv) `z' for scrolling through the buffer, and
26 v) BSD line addressing syntax (i.e., `^' and `%') is recognized.
27
282) If crypt(3) is available, files can be read and written using DES
29 encryption. The `x' command prompts the user to enter a key used for
30 encrypting/ decrypting subsequent reads and writes. If only a newline
31 is entered as the key, then encryption is disabled. Otherwise, a key
32 is read in the same manner as a password entry. The key remains in
33 effect until encryption is disabled. For more information on the
34 encryption algorithm, see the bdes(1) man page. Encryption/decryption
35 should be fully compatible with SunOS des(1).
36
373) The POSIX interactive global commands `G' and `V' are extended to
38 support multiple commands, including `a', `i' and `c'. The command
39 format is the same as for the global commands `g' and `v', i.e., one
40 command per line with each line, except for the last, ending in a
41 backslash (\).
42
434) An extension to the POSIX file commands `E', `e', `r', `W' and `w' is
44 that <file> arguments are processed for backslash escapes, i.e., any
45 character preceded by a backslash is interpreted literally. If the
46 first unescaped character of a <file> argument is a bang (!), then the
47 rest of the line is interpreted as a shell command, and no escape
48 processing is performed by ed.
49
505) For SunOS ed(1) compatibility, ed runs in restricted mode if invoked
51 as red. This limits editing of files in the local directory only and
52 prohibits shell commands.
53
54DEVIATIONS
55----------
561) Though ed is not a stream editor, it can be used to edit binary files.
57 To assist in binary editing, when a file containing at least one ASCII
58 NUL character is written, a newline is not appended if it did not
59 already contain one upon reading. In particular, reading /dev/null
60 prior to writing prevents appending a newline to a binary file.
61
62 For example, to create a file with ed containing a single NUL character:
63 $ ed file
64 a
65 ^@
66 .
67 r /dev/null
68 wq
69
70 Similarly, to remove a newline from the end of binary `file':
71 $ ed file
72 r /dev/null
73 wq
74
752) Since the behavior of `u' (undo) within a `g' (global) command list is
76 not specified by POSIX, it follows the behavior of the SunOS ed:
77 undo forces a global command list to be executed only once, rather than
|
87 written as:
88 ed - file <<EOF
89 1g/.*/u\
90 ,s/censor1//g\
91 ,s/censor2//g
92 ...
93
943) The `m' (move) command within a `g' command list also follows the SunOS
95 ed implementation: any moved lines are removed from the global command's
96 `active' list.
97
984) If ed is invoked with a name argument prefixed by a bang (!), then the
99 remainder of the argument is interpreted as a shell command. To invoke
100 ed on a file whose name starts with bang, prefix the name with a
101 backslash.
| 87 written as:
88 ed - file <<EOF
89 1g/.*/u\
90 ,s/censor1//g\
91 ,s/censor2//g
92 ...
93
943) The `m' (move) command within a `g' command list also follows the SunOS
95 ed implementation: any moved lines are removed from the global command's
96 `active' list.
97
984) If ed is invoked with a name argument prefixed by a bang (!), then the
99 remainder of the argument is interpreted as a shell command. To invoke
100 ed on a file whose name starts with bang, prefix the name with a
101 backslash.
|