redo(3f) - [M_history] Fortran-based Input History Editor (LICENSE:MIT)
CONTENTS
Synopsis
Description
Options
Usage
Listing Command History
Positioning To Previous Commands
Editing The Current Buffer Line
Help
System Commands
Dumping And Loading The Command History
Example Program
Sample Usage
Author
License
subroutine redo(inputline,r)
character(len=*) :: inputline
character(len=1),intent(in),optional :: r
the redo(3f) routine lets you recall, list, save, and modify previously entered program input. Built-in help is included.
The redo(3f) input history editor is a simple-to-use input history editor interface modeled on the CDC NOS command REDO. It uses a line
editor model that means no special escape characters or control characters are required. Typically, only a few minutes are required to master
usage.
When using redo(3f) input lines are usually first read into a character variable and then passed to the routine. The returned string can
then be parsed or read from with an internal READ(3f). So, for example, if you have an existing READ(3f) such as
READ(*,101) A,I,K
replace it with something similar to
USE M_HISTORY,ONLY : REDO
CHARACTER(LEN=255) :: LINE ! make variable big enough to read a line
:
:
READ(*,'(A)') LINE ! read line into character variable
CALL REDO(LINE) ! pass line to REDO(3f). This is a no-op except
! for storing the line into the input history
! unless the input line is the "r" command
READ(LINE,101)A,I,K ! read from variable like you did from file
| inputline |
line to record into history buffer file or to edit. |
| r |
Optional character to use as command to invoke editing. Defaults to 'r'. |
When prompted for an input line by your program you may at any time enter "r" on a line by itself, or a line beginning with "r r_command" and you
will enter the command history edit mode. Now you can recall and edit previous input or compose an input line using the editor commands.
By default, you will be editing the last line you entered, shifted one character to the right by an exclamation character.
The character you respond with in column one controls what happens next.
| o |
If you enter "?" while in command edit mode, help is displayed. |
| o |
If the last input line is not the desired line to edit, select the line to edit by entering its line number or by using the /,l,u, and d
commands (see below for details) to find the desired input line. |
| o |
Next enter an editing directive (c,m) to edit the selected line. The "change" command will change all occurrences of an old string to a new
string ... |
c/old/new/
| o |
or the "modify" command can be used with the special characters # & and ^ ...
| o |
A # under a character will delete a character. |
| o |
An "&" (ampersand) will cause the character above it to be replaced with a space. |
| o |
To insert a string enter ^string#. |
| o |
Otherwise, enter a character under one in the currently displayed command and it will replace it. |
| o |
hit RETURN to start another edit of the line |
|
| o |
Once the change is executed you will be prompted for another edit directive |
| o |
You will stay in edit mode until you enter a return on a blank line to feed your line to your program; or enter "." or "q" (which means
cancel changes and return a blank line). |
A detailed summary of the main edit-mode commands follows. In the descriptions, N stands for a number ...
| l|p N |
list from line N. -N shows N last lines |
| L|P N |
same as 'l' except no line numbers (for pasting) |
| /string |
search for simple string in all history lines |
Note that the buffer is set to the last line displayed
| u N |
up through buffer |
| d N |
down through buffer |
| N |
load line number |
| c/oldstring/newstring/ |
change all occurrences of old string to new string. Note that s (for substitute) is a synonym for c (for change).
For the "c" directive the second character becomes the delimiter. Traditionally one usually uses a delimiter of / unless the string you are
editing contains /.
|
| mmod_string |
If the first character of your entry is m or blank,
| o |
REPLACE a string by entering a replacement character under it |
| o |
LEAVE a character alone by leaving a space under it |
| o |
DELETE a character by putting a # character under it |
| o |
BLANK OUT a character by putting an & under it |
| o |
INSERT A STRING by entering ^STRING# |
|
| The "modify" directive takes a little practice but this single directive accommodates positionally deleting, replacing, and
inserting text. it is hardest using "modify" to put the strings "&" and "#" into your lines. to put a # or & character into a string use
the 'c' command instead or ^� or ^##. |
| ;N N N N ... |
Append specified lines to current line |
| !cmd |
execute system command |
| w FILENAME |
write entire command history to specified file |
| r FILENAME |
replace command history with file contents |
| a FILENAME |
append lines from file onto command history |
Sample program
program demo_redo
use M_history, only : redo
implicit none
character(len=1024) :: line
integer :: ios
integer :: cstat
character(len=256) :: sstat
write(*,'(a)') &
& 'REDO(3f) COMMAND INPUT EDITOR', &
& 'enter "r" or "r r_command" on the input line to go', &
& 'into history edit mode. Once in history edit mode you', &
& 'may enter "?" to get some help. Enter "quit" to exit', &
& 'the program.'
do
write(*,'(a)',advance='no')'>->' ! write prompt
read(*,'(a)',iostat=ios) line ! read new input line
! if "r", edit and return a line from the history editor
call redo(line) ! store into history if not "r".
if(line.eq.'quit')stop ! exit program if user enters "quit"
! now call user code to process new line of data
! As an example, call the system shell
call execute_command_line(trim(line),cmdstat=cstat,cmdmsg=sstat)
enddo
end program demo_redo
The example program is basically a loop that reads a command from standard input and then executes it as a subshell unless the "r" command is
entered.
Now, we will enter an echo(1) command followed by a few other lines of input. Then we recall the echo(1) command and use a few of
the features of redo(3) to change and then re-execute the command.
>echo This isss a Test
This isss a Test
>date
Sun May 31 23:54:09 EDT 2009
>pwd
/cygdrive/c/urbanjs/MYCYGWIN/DISKA/public_html/public/CLONE/REDO
>r ! enter edit mode
00001 echo This isss a Test ! last commands are displayed
00002 date
00003 pwd
!pwd
>1 ! go to first line in history
!echo This isss a Test
## t ! delete and replace characters
!echo This is a test ! insert a string
^new #
!echo This is a new test
c/test/TEST/ ! change a substring
!echo This is a new TEST
& | replace character with spaces
!echo This is a newTEST
! a blank line ends editing
This is a newTEST
>quit
John S. Urban, 1988,2009,2011,2015 (last change: Nov 2019)
MIT
