self-deleting shell script
BashShellBash Problem Overview
I've looked around for an answer to this one but couldn't find one.
I have written a simple script that does initial server settings and I'd like it to remove/unlink itself from the root directory on completion. I've tried a number of solutions i googled ( for example /bin/rm $test.sh) but the script always seems to remain in place. Is this possible? Below is my script so far.
#! /bin/bash
cd /root/
wget -r -nH -np --cut-dirs=1 http://myhost.com/install/scripts/
rm -f index.html* *.gif */index.html* */*.gif robots.txt
ls -al /root/
if [ -d /usr/local/psa ]
then
echo plesk > /root/bin/INST_SERVER_TYPE.txt
chmod 775 /root/bin/*
/root/bin/setting_server_ve.sh
rm -rf /root/etc | rm -rf /root/bin | rm -rf /root/log | rm -rf /root/old
sed -i "75s/false/true/" /etc/permissions/jail.conf
exit 1;
elif [ -d /var/webmin ]
then
echo webmin > /root/bin/INST_SERVER_TYPE.txt
chmod 775 /root/bin/*
/root/bin/setting_server_ve.sh
rm -rf /root/etc | rm -rf /root/bin | rm -rf /root/log | rm -rf /root/old
sed -i "67s/false/true/" /etc/permissions/jail.conf
break
exit 1;
else
echo no-gui > /root/bin/INST_SERVER_TYPE.txt
chmod 775 /root/bin/*
/root/bin/setting_server_ve.sh
rm -rf /root/etc | rm -rf /root/bin | rm -rf /root/log | rm -rf /root/old
sed -i "67s/false/true/" /etc/permissions/jail.conf
break
exit 1;
fi
Bash Solutions
Solution 1 - Bash
rm -- "$0"
Ought to do the trick. $0 is a magic variable for the full path of the executed script.
Solution 2 - Bash
This works for me:
#!/bin/sh
rm test.sh
Maybe you didn't really mean to have the '$' in '$test.sh'?
Solution 3 - Bash
The script can delete itself via the shred command (as a secure deletion) when it exits.
#!/bin/bash
currentscript="$0"
# Function that is called when the script exits:
function finish {
echo "Securely shredding ${currentscript}"; shred -u ${currentscript};
}
# Do your bashing here...
# When your script is finished, exit with a call to the function, "finish":
trap finish EXIT
Solution 4 - Bash
The simplest one:
#!/path/to/rm
Usage: ./path/to/the/script/above
Note: /path/to/rm
must not have blank characters at all.
Solution 5 - Bash
$0
may not contain the script's name/path in certain circumstances. Please check the following: <https://stackoverflow.com/a/35006505/5113030> (Choosing between $0 and BASH_SOURCE...)
The following script should work as expected in these cases:
source script.sh
- the script is sourced;./script.sh
- executed interactively;/bin/bash -- script.sh
- passed as an argument to a shell program.
#!/usr/bin/env bash
# ...
rm -- "$( readlink -f -- "${BASH_SOURCE[0]:-$0}" 2> '/dev/null'; )";
Please check the following regarding shell script source reading and execution since it may affect the behavior when a script is deleted while running: <https://unix.stackexchange.com/a/121025/133353> (How Does Linux deal with shell scripts?...)
Related: <https://stackoverflow.com/a/246128/5113030> (How can I get the source directory of a Bash script from...)
Solution 6 - Bash
I wrote a small script that adds a grace period to a self deleting script based on
user742030's answer https://stackoverflow.com/a/34303677/10772577.
function selfShred {
SHREDDING_GRACE_SECONDS=${SHREDDING_GRACE_SECONDS:-5}
if (( $SHREDDING_GRACE_SECONDS > 0 )); then
echo -e "Shreding ${0} in $SHREDDING_GRACE_SECONDS seconds \e[1;31mCTRL-C TO KEEP FILE\e[0m"
BOMB="●"
FUZE='~'
SPARK="\e[1;31m*\e[0m"
SLEEP_LEFT=$SHREDDING_GRACE_SECONDS
while (( $SLEEP_LEFT > 0 )); do
LINE="$BOMB"
for (( j=0; j < $SLEEP_LEFT - 1; j++ )); do
LINE+="$FUZE"
done
LINE+="$SPARK"
echo -en $LINE "\r"
sleep 1
(( SLEEP_LEFT-- ))
done
fi
shred -u "${0}"
}
trap selfShred EXIT
See the repo here: https://github.com/reedHam/self-shred
Solution 7 - Bash
Why remove the script at all? As other have mentioned it means you have to keep a copy elsewhere.
A suggestion is to use a "firstboot" like approach. Simply create an empty file in e.g. /etc/sysconfig that triggers the execution of this script if it is present. Then remove that file at the end of the script.
Modify the script so it has the necessary chkconfig headers and place it in /etc/init.d/ so it is run at every boot.
That way you can rerun the script at a later time simply by recreating the trigger script.
Hope this helps.