Prefix with shellscript check
The shellscript check, that can be used to prefix any command line may look like this,
#!/bin/bash
if [ "$1" == "--debug" ]
then
debug=true
shift
else
debug=false
fi
"$@" & pid=$!
sleep 0.1 # time (s) until kill
kill $pid 2> /dev/null
res="$?"
if $debug
then
if [ $res -eq 0 ]
then
echo "killed at time-out: $@"
else
echo "finished gracefully: $@"
fi
fi
Example 1
$ ./check --debug bash -c "while true;do date '+%s.%N';sleep 0.01;done"
1634944386.589977656
1634944386.603126888
1634944386.616089924
1634944386.629058026
1634944386.642334480
1634944386.655644267
1634944386.668289318
1634944386.681058710
killed at time-out: bash -c while true;do date '+%s.%N';sleep 0.01;done
Example 2
$ ./check --debug lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 238,5G 0 disk
├─sda1 8:1 0 500M 0 part
├─sda2 8:2 0 139,4G 0 part
├─sda3 8:3 0 1000M 0 part
├─sda4 8:4 0 1K 0 part
├─sda5 8:5 0 89,7G 0 part /
└─sda6 8:6 0 8G 0 part [SWAP]
sdb 8:16 0 3,7T 0 disk
├─sdb1 8:17 0 510M 0 part
├─sdb2 8:18 0 30G 0 part
├─sdb5 8:21 0 1M 0 part
├─sdb6 8:22 0 100G 0 part
├─sdb7 8:23 0 3,5T 0 part /media/multimed-2
└─sdb8 8:24 0 5G 0 part
sr0 11:0 1 1024M 0 rom
nvme0n1 259:0 0 232,9G 0 disk
├─nvme0n1p1 259:1 0 232,9G 0 part
└─nvme0n1p2 259:2 0 1M 0 part
finished gracefully: lsblk
Primitive custom shell psh
Another alternative, a primitive home-mode shell psh can be used for this purpose too.
Advantage: You can run the commands directly without any extra prefix.
Disadvantages: You can edit the command line, but there is no history and you have no access to the history of a standard shell, for example bash, zsh, tcsh`). Several other features of a the standard shell are missing too.
The bash shellscript psh and the python3 script pin should be made executable and copied, moved or linked into a directory in PATH, for example /usr/local/bin,
Start psh, run commands and exit from it with exit. The input is managed by pin, that uses readline in order to make it possible to edit the command line (more advanced than the built-in command read of bash).
psh,
#!/bin/bash
tmpf=$(mktemp)
curdir="$(pwd)"
cmd=
while true
do
# read -p "psh:$curdir> " cmd 2>&1
# echo "$cmd" > "$tmpf"
pin "$curdir" "$tmpf"
# cat "$tmpf"
cmd=$(cat "$tmpf")
if [ "$cmd" != "exit" ]
then
if [ "${cmd:0:3}" == "cd " ]
then
source "$tmpf"
curdir="$(pwd)"
else
source "$tmpf" & pid=$!
sleep 0.1 # time (s) until kill
kill $pid 2> /dev/null
fi
else
break
fi
done 2> /dev/null
rm "$tmpf"
pin,
#!/usr/bin/python3
from sys import argv
import rlcompleter
import readline
readline.parse_and_bind("tab: complete")
prompt = 'psh:{0} > '.format(argv[1])
f = open(argv[2], 'w')
cmd = input(prompt)
f.write('{0}\n'.format(cmd)) # write to first argument
Example:
sudodus@bionic64 /media/multimed-2/test/test0/temp/PeterElbert $ psh
psh:/media/multimed-2/test/test0/temp/PeterElbert > while true;do date '+.%N';sleep 0.008;done
.753302869
.763750113
.773720876
.783983502
.794652755
.805570413
.816651252
.827621482
.838553391
.849516607
psh:/media/multimed-2/test/test0/temp/PeterElbert > ls -l
totalt 12
-rwxrwxr-x 1 sudodus sudodus 282 okt 23 01:18 check
-rwxrwxr-x 1 sudodus sudodus 255 okt 23 07:18 pin
-rwxrwxr-x 1 sudodus sudodus 438 okt 23 07:51 psh
psh:/media/multimed-2/test/test0/temp/PeterElbert > cd ..
psh:/media/multimed-2/test/test0/temp > exit
sudodus@bionic64 /media/multimed-2/test/test0/temp/PeterElbert $
