---------- Here's the pseudo code of what I had in mind:- Initialise
TopLine AsSelected

Perhaps this previous post didn't get sent ?
Linux shell programming encourages successive refinement, which is
good, but it also encourages hacking instead of designing.
So please refine my version 4 -- below.
==================== I previously wrote:-
I understand that VT cursors can't 'step-up to a previously written line' ?
So to acheive the effect of 'selecting higher-lines' a screen re-write is needed?

---------- Here's the pseudo code of what I had in mind:-
Initialise TopLine AsSelected

REPEAT

write the 1st 8 directory entries, one per line and
mark the SelectedEntry, by some visible means, eg. a leading "->"

CASE ValidKey OF
"v" : IF SelectedEntry = FileType THEN less SelectedEntry END;
CR>: IF SelectedEntry = FileType THEN Editor SelectedEntry
ELSE cd SelectedEntry END;
UNTIL ValidKey = "q"
-----------------
How would I start towards such a utility using only bash ?

== TIA

##!/bin/bash
#Oct 2009 > file manager to navigate dir-tree, view, edit, mkdir, cp,..etc.
# can replace 'nano' by own editor & 'w3m' by lynx, links ..etc.

write_menu ()

{

clear
# echo 'numbered lines of dir:-'
pwd

# add line-no & show some fields of 'ls -l'
ls -l |
awk '{print NR "\t" $1 " : " $5 " : " $9 }'

echo -n "Selection file/dir: "
read SELCTN

# extract the file/dir via the line-no/SELECTN
FileDir=` ls -l |
awk -v dirline="$SELCTN" 'NR==dirline { print $9 }' `

echo 'L[ynx, V[iew, E[dit, cD[ir', Q[uit, M[kdir, C[opy, U[cd ../
read ACTION
case $ACTION in
L | l) w3m $FileDir;;

U | u) cd ../;;
V | v) cat $FileDir;;
E | e) nano $FileDir;;
# for new file, nano allows chosen fileName to be entered at (no spam) 1st 'save'
D | d) cd $FileDir;;
M | m) echo -n 'new-dir name: '; read KEY; mkdir $KEY;;

C | c) echo -n 'dest-file-name: '; read KEY; cp $FileDir $KEY;;
Q | q) exit;;

*) echo -n "an unknown number of";;
esac
echo -n 'pwd=' ; pwd ;

}

until TEST-COMMANDS; do
#CONSEQUENT-COMMANDS;
write_menu
echo 'key to continue'
read Cont;

done

On 2009-10-31, no.top.post at (no spam) gmail.com wrote:
Perhaps this previous post didn't get sent ?
Linux shell programming encourages successive refinement, which is
good, but it also encourages hacking instead of designing.
So please refine my version 4 -- below.
==================== I previously wrote:-
I understand that VT cursors can't 'step-up to a previously written line' ?
So to acheive the effect of 'selecting higher-lines' a screen re-write is needed?

printf '\e[A' ## move up one line
printf '\e[5A' ## move up two lines

I understand that VT cursors can't 'step-up to a previously written line' ?
So to acheive the effect of 'selecting higher-lines' a screen re-write is needed?

printf '\e[A' ## move up one line
printf '\e[5A' ## move up five lines

Wow ! But I realised that even if I could hi-lite the stepped-up-to

--snip --
clear
# echo 'numbered lines of dir:-'
pwd
More portable is:

printf 'new-dir name: '; read KEY; mkdir "$KEY" ;;

In bash:

read -ep 'new-dir name: ' KEY; mkdir "$KEY" ;;

OK, I'll try that.
Don't forget to check that mkdir succeeded and deal with failure.

OK but, a main beauty of mc-like-apps is the visual feedback.

--snip --
echo -n 'pwd=' ; pwd ;

POSIX shells have a PWD variable:

printf "%s" "$PWD"

In article <7l3ffiF3bvl3gU1 at (no spam) mid.individual.net>, "Chris F.A. Johnson"
cfajohnson at (no spam) gmail.com> wrote:

I understand that VT cursors can't 'step-up to a previously written
line' ? So to acheive the effect of 'selecting higher-lines' a screen
re-write is needed?

printf '\e[A' ## move up one line
printf '\e[5A' ## move up five lines

Wow ! But I realised that even if I could hi-lite the stepped-up-to
line, it would be very difficult to map the cursor position to the
directory file/dir name. Altho' perhaps not ? It's amazing how 'writing
a formal description of the task' sometimes reveals a possible
algorithm? Counting the multiple '\e[A' would tell the tell the
position in the "ls -l" list just as well as entering the number
manually does.
I think I've got the char-sequence to hi-lite or reverse-video,
somewhere.
--snip --
clear
# echo 'numbered lines of dir:-'
pwd
More portable is:

printf 'new-dir name: '; read KEY; mkdir "$KEY" ;;

In bash:

read -ep 'new-dir name: ' KEY; mkdir "$KEY" ;;

OK, I'll try that.
Don't forget to check that mkdir succeeded and deal with failure.

OK but, a main beauty of mc-like-apps is the visual feedback. You
can/should confirm seeing your creations/intentions. I favour automation
which includes the human in the loop. It's also nice to have some
control, instead of that other OS's wizard things, or as I've recently
discovered like Debian's Stalinist-school-teacher style.
--snip --
echo -n 'pwd=' ; pwd ;

POSIX shells have a PWD variable:

printf "%s" "$PWD"

Thanks for the feedback. It's nice to learn/improve in small
increments.

== Chris Glur.