| 1 |
227 |
jeremybenn |
rlfe (ReadLine Front-End) is a "universal wrapper" around readline.
|
| 2 |
|
|
You specify an interactive program to run (typically a shell), and
|
| 3 |
|
|
readline is used to edit input lines.
|
| 4 |
|
|
|
| 5 |
|
|
There are other such front-ends; what distinguishes this one is that
|
| 6 |
|
|
it monitors the state of the inferior pty, and if the inferior program
|
| 7 |
|
|
switches its terminal to raw mode, then rlfe passes your characters
|
| 8 |
|
|
through directly. This basically means you can run your entire
|
| 9 |
|
|
session (including bash and terminal-mode emacs) under rlfe.
|
| 10 |
|
|
|
| 11 |
|
|
FEATURES
|
| 12 |
|
|
|
| 13 |
|
|
* Can use all readline commands (and history) in commands that
|
| 14 |
|
|
read input lines in "canonical mode" - even 'cat'!
|
| 15 |
|
|
|
| 16 |
|
|
* Automatically switches between "readline-editing mode" and "raw mode"
|
| 17 |
|
|
depending on the terminal mode. If the inferior program invokes
|
| 18 |
|
|
readline itself, it will do its own line editing. (The inferior
|
| 19 |
|
|
readline will not know about rlfe, and it will have its own history.)
|
| 20 |
|
|
You can even run programs like 'emavs -nw' and 'vi' under rlfe.
|
| 21 |
|
|
The goal is you could leave rlfe always on without even knowing
|
| 22 |
|
|
about it. (We're not quite there, but it works tolerably well.)
|
| 23 |
|
|
|
| 24 |
|
|
* The input line (after any prompt) is changed to bold-face.
|
| 25 |
|
|
|
| 26 |
|
|
INSTALL
|
| 27 |
|
|
|
| 28 |
|
|
The usual: ./configure && make && make install
|
| 29 |
|
|
|
| 30 |
|
|
Note so far rlfe has only been tested on GNU Linux (Fedora Core 2)
|
| 31 |
|
|
and Mac OS X (10.3).
|
| 32 |
|
|
|
| 33 |
|
|
This assumes readline header files and libraries are in the default
|
| 34 |
|
|
places. If not, you can create a link named readline pointing to the
|
| 35 |
|
|
readline sources. To link with libreadline.a and libhistory.a
|
| 36 |
|
|
you can copy or link them, or add LDFLAGS='-/path/to/readline' to
|
| 37 |
|
|
the make command-line.
|
| 38 |
|
|
|
| 39 |
|
|
USAGE
|
| 40 |
|
|
|
| 41 |
|
|
Just run it. That by default runs bash. You can run some other
|
| 42 |
|
|
command by giving it as command-line arguments.
|
| 43 |
|
|
|
| 44 |
|
|
There are a few tweaks: -h allows you to name the history file,
|
| 45 |
|
|
and -s allows you to specify its size. It default to "emacs" mode,
|
| 46 |
|
|
but if the the environment variable EDITOR is set to "vi" that
|
| 47 |
|
|
mode is chosen.
|
| 48 |
|
|
|
| 49 |
|
|
ISSUES
|
| 50 |
|
|
|
| 51 |
|
|
* The mode switching depends on the terminal mode set by the inferior
|
| 52 |
|
|
program. Thus ssh/telnet/screen-type programs will typically be in
|
| 53 |
|
|
raw mode, so rlfe won't be much use, even if remote programs run in
|
| 54 |
|
|
canonical mode. The work-around is to run rlfe on the remote end.
|
| 55 |
|
|
|
| 56 |
|
|
* Echo supression and prompt recognition are somewhat fragile.
|
| 57 |
|
|
(A protocol so that the o/s tty code can reliably communicate its
|
| 58 |
|
|
state to rlfe could solve this problem, and the previous one.)
|
| 59 |
|
|
|
| 60 |
|
|
* See the intro to rlfe.c for more notes.
|
| 61 |
|
|
|
| 62 |
|
|
* Assumes a VT100-compatible terminal, though that could be generalized
|
| 63 |
|
|
if anybody cares.
|
| 64 |
|
|
|
| 65 |
|
|
* Requires ncurses.
|
| 66 |
|
|
|
| 67 |
|
|
* It would be useful to integrate rlfe's logic in a terminal emulator.
|
| 68 |
|
|
That would make it easier to reposition the edit position with a mouse,
|
| 69 |
|
|
integrate cut-and-paste with the system clipboard, and more robustly
|
| 70 |
|
|
handle escape sequence and multi-byte characters more robustly.
|
| 71 |
|
|
|
| 72 |
|
|
AUTHOR
|
| 73 |
|
|
|
| 74 |
|
|
Per Bothner
|
| 75 |
|
|
|
| 76 |
|
|
LICENSE
|
| 77 |
|
|
|
| 78 |
|
|
GPL.
|
