Can't write to file with script - linux

I have written a script that is supposed to run some commands, reboot my ubuntu server and then after the server boots up, resume operation, and removes the entry from the bash file.
I have been trying for hours to figure out why my script won't write to .bashrc (or any file for that matter). Testing the commands individually works just fine. However, when run through my script nothing is written to the file. At this point I am stumped and would really like a fresh pair of eyes to help as I am sure the reason is silly and probably something I am missing. This would be my first script so sorry if this ends up being a stupid question. I put the "sudo reboot command in a comment so I won't have to reboot each time.
The script's name is test.sh and is run from ~/ . I hope this is clear and I didn't miss anything.
#!/bin/bash
echo "Script initiating"
#condition for script to run after reboot, created later on
if [ ! -f /var/run/bootflag ]; then
echo "First run"
script="bash ~/test.sh"
#this will add the script in the bash file so it will be ran on next boot
echo "$script" >> ~/.bashrc
echo "bash entry added"
#creating flag file to check if this is a second run
sudo touch /var/run/bootflag
echo "Flag created"
echo "Rebooting..."
#sudo reboot
else
echo "resuming script..."
echo "cleaning up..."
#remove the bash entry by replacing it with a space
sed -i '/bash/d' ~/.bashrc
echo "bash entry removed"
#remove the boot flag
sudo rm -f /var/run/bootflag
echo "bootflag removed"
echo "running commands post-reboot"
#commands here
echo "script exiting"
fi

I finally figured it out.
Because I was running the script with sudo, the script would take the relative path ~/.bashrc for the root user. The script was working fine all along, I was just looking at my user's .bashrc and was expecting things to appear, when all along the root user's .bashrc file was being written in.
I used sudo inside the script for all elevated commands and run the script normally without sudo and there it is, working as expected.
As I thought, this was beyond silly after all. At least I learned something today.
Thank you all for taking the time to reply and help, I really appreciate it.

Related

Is it possible to auto reboot for 5 loops through mint?

I am currently using the following command to run reboot
sudo shutdown -r now
however, I would need to run it for 5 loops before and after executing some other programs. Was wondering if it is possible to do it in MINT environment?
First a disclaimer: I haven't tried this because I don't want to reboot my machine right now...
Anyway, the idea is to make a script that can track it's iteration progress to a file as #david-c-rankin suggested. This bash script could look like this (I did test this):
#!/bin/sh
ITERATIONS="5"
TRACKING_FILE="/path/to/bootloop.txt"
touch "$TRACKING_FILE"
N=$(cat "$TRACKING_FILE" | wc -c)
if [ "$N" -lt "$ITERATIONS" ]; then
printf "." >> "$TRACKING_FILE"
echo "rebooting (iteration $N)"
# TODO: this is where you put the reboot command
# and anything you want to run before rebooting each time
else
rm "$TRACKING_FILE"
# TODO: other commands to resume anything required
fi
Then add a call to this script somewhere where it will be run on boot. eg. cron (#reboot) or systemd. Don't forget to remove it from a startup/boot command when you're finished or next time you reboot, it will reboot N times.
Not sure exactly how you are planning on using it, but the general workflow would look like:
save script to /path/to/reboot_five_times.sh
add script to run on boot (cron, etc.)
do stuff (manually or in a script)
call the script
computer reboots 5 times
anything in the second TODO section of the script is then run
go back to step 3, or if finished remove from cron/systemd so it won't reboot when you don't want it to.
First create a text document wherever you want,I created one on Desktop,
Then use this file as a physical counter and write a daemon file to run things at startup
For example:
#!/bin/sh
var=$(cat a.txt)
echo "$var"
if [ "$var" != 5 ]
then
var=$((var+1))
echo "$var" > a.txt
echo "restart here"
sudo shutdown -r now
else
echo "stop restart"
echo 0 > a.txt
fi
Hope this helps
I found a way to create a file at startup for my reboot script. I incorporated it with the answers provided by swalladge and also shubh. Thank you so much!
#!/bin/bash
#testing making a startup application
echo "
[Desktop Entry]
Type=Application
Exec=notify-send success
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name[en_CA]=This is a Test
Name=This is a Test
Comment[en_CA]=
Comment=" > ~/.config/autostart/test.desktop
I create a /etc/rc.local file to execute user3089519's script, and this works for my case. (And for bootloop.txt, I put it here: /usr/local/share/bootloop.txt )
First: sudo nano /etc/rc.local
Then edit this:
#!/bin/bash
#TODO: things you want to execute when system boot.
/path/to/reboot_five_times.sh
exit 0
Then it works.
Don't forget edit /etc/rc.local and remove /path/to/reboot_five_times.sh when you done reboot cycling.

Why doesn't $(which node) work inside a cron job executing a BASH shell?

According to this answer the reason cron doesn't have access to environment variables normally associated with a BASH terminal is because it doesn't source the users .bashrc file.
I have a script which does source my .bashrc file but it still fails to find my currently in use version of Node (meaning I need to list the full directory and change it with every update!).
Script:
#!/bin/bash
source $HOME/.bashrc # <-- even after sourcing .bashrc, '$(which node)' returns nothing
NODE="$(which node)" # <-- output is blank in cron job
PROCESS="/home/grayedfox/.nvm/versions/node/v8.9.4/bin/node /home/grayedfox/github/blockscrape/main.js"
LOGFILE="/tmp/log.out"
export BLOCKSCRAPECLI="/opt/litecoin-0.14.2/bin/litecoin-cli"
if pgrep -f "$PROCESS" > /dev/null; then
echo "Blockscrape is doing it's thing - moving on..." >> $LOGFILE
else
echo "Blockscrape not running! Starting again..." >> $LOGFILE
echo "Process: $PROCESS" >> $LOGFILE
echo "Node: $NODE" >> $LOGFILE # <-- outputs only 'Node: ' in log file
$PROCESS >> $LOGFILE
fi
Crontab:
# make default shell BASH
SHELL=/bin/bash
# reboots litecoin daemon if it dies
#reboot /opt/litecoin-0.14.2/bin/litecoind
# check every minute to see if block scrape running and restart it if not
* * * * * /home/grayedfox/github/blockscrape/restartBlockscrape.sh
I can confirm that node (and doing "which node") works fine in my terminal.
Thanks for the help!
As discussed in this answer - thethis answer problem was that in Ubuntu 16.04 (and many prior versions) the standard .bashrc file quits if it's not being run interactively.
Commenting out the below code from my bash file fixed it:
# If not running interactively, don't do anything
case $- in
*i*) ;;
*) return;;
esac

Script runs fully when ran manually but misses commands when ran from another script

I have 2 scripts that I'm testing to automate starting services on my server however they behave weirdly.
The first script is
#!/bin/sh
screen -dmS Test_Screen
sleep 1
sudo sh cd.sh
echo "finished"
Which runs perfectly however the script it runs does not and is as follows
#!/bin/sh
screen -S Test_Screen -X stuff "cd /home/Test"
sleep 1
screen -S Test_Screen -X eval "stuff \015"
sleep 1
echo "Complete"
The second script will run perfect if I run it from command line and will CD into the directory within the screen. However, if it runs from the first script it Will Not CD into the correct directory within the screen, but it will still print "Complete".
I'm Using CENTOS 6.7 and the latest version of GNU screen
Any Ideas?
This seems to be a problem with session nesting.
In your first script you create a session named Test_Screen.
In your second script the -S parameter tells screen to create a session of the same name. This might cause screen to exit and not cd into the correct directory.
You could move the cd command in front of the sudo sh cd.sh and remove those screen calls from the second script leaving only
stuff \015
echo "Complete"
Using the correct screenflags should also work.
#!/bin/sh
screen -dr Test_Screen -X stuff "cd /home/Test"
sleep 1
screen -dr Test_Screen -X eval "stuff \015"
sleep 1
echo "Complete"
For a more modern alternative to screen, have a look at tmux.
Ok so this turned out really weird. After posting i tried a couple of things on a centos 6.7 hyper V test environment and got the exact same issue. However, later in the day we ended up changing service provider and upgrading to centos 7 in the process. I am not sure why but since the update the script now runs perfectly and i was able to actually merge the two scripts into one in order to make it more efficient. If anyone knows why the update fixed it feel free to let me know.

non-shell command running inside shell script

I am trying to run a non shell script command inside a .sh script.
Current code looks like this :
#!/bin/bash
echo "Enter name of the folder you want to join!"
read folder
cd ~/domains/name/public_html/$folder/sites/default/
echo "enabling u7seven theme!"
drush en u7seven -y;
echo "disabling overlay!"
drush dis overlay -y;
echo "running all-folder script!"
u7d7up all-folder
Code that is not a shell code(which is local script somewhere on the server is ):
u7d7up all-folder
However, if I go and manually call this functionu7d7up all-folder from site root it works.
Since I am having more than 10 sites, i'd like to just call the script without entering and doing all these commands manually.
You might be facing an issue due to non-presence of u7d7up in the $PATH variable.
A robust way to write your script will be put the absolute path of the u7d7up; also you would need to check for the permissions on it.
#!/bin/bash
echo "Enter name of the folder you want to join!"
read folder
cd ~/domains/name/public_html/$folder/sites/default/
echo "enabling u7seven theme!"
drush en u7seven -y;
echo "disabling overlay!"
drush dis overlay -y;
echo "running all-folder script!"
/absolute-path-to/u7d7up /absolute-path-to/all-folder

Linux Ubuntu: Script works in terminal, but not .sh

Issue Summary: My script works as it should when typed into the terminal, however, it does not work correctly when executed in terminal from a .sh file, why is this?
Script:
echo World of Clucky - Frisnuk "\033]0;Frisnuk - World of Clucky\a"
#! /usr/bin/env bash
BINDIR="$(dirname "$(readlink -fn "$0")")"
cd "$BINDIR"
while true
do
source /home/clucky/MinecraftServers/Frisnuk/serverconfig/config.sh
#Start Server
java -Xms2000M -Xmx2000M -jar $serverjar.jar nogui
if [ "`date +%w%H`" = "001" ]
then
#Delete map files for The End
rm -R /Frisnuk_the_end
echo "End has been successfully reloaded"
echo "[`date +%D\ %T`] End Reloaded" >> /home/clucky/MinecraftServers/Frisnuk/EndRestart.txt
#Change Item of The Week
weekofyear=`date +%y\-%U`
s=$(<serverconfig/ItemofTheWeek/item$weekofyear.txt)
set -- $s
itemoftheweekid=$2
itemoftheweekprice=$3
xmlstarlet edit -L -u "/scs-shop/itemStack[#type='double']" -v $itemoftheweekid /plugins/ShowCaseStandalone/ffs-storage/ffss_cac8480951254352116d5255e795006252d404d8
xmlstarlet edit -L -u "/scs-shop/price[#type='double']" -v $itemoftheweekprice /plugins/ShowCaseStandalone/ffs-storage/ffss_cac8480951254352116d5255e795006252d404d8
fi
echo "If you want to stop the restart and shut the server off instead, please press Ctrl+C at this time"
for i in 5 4 3 2 1
do
echo "$i..."
sleep 1
done
echo "Restarting Server"
clear
done
Instead of working and running the server, it just says this:
World of Clucky - Frisnuk
/home/clucky/MinecraftServers/Frisnuk/craftminecraft.sh: 7: /home/clucky/MinecraftServers/Frisnuk/craftminecraft.sh: source: not found
Error: Unable to access jarfile .jar
If you want to stop the restart and shut the server off instead, please press Ctrl+C at this time
5...
4...
3...
2...
1...
I am going to take a shower shortly, but I will be returning either later tonight, or tomorrow morning. Thank you in advanced for your assistance.
You put an echo before the shebang, so your script is being interpreted by dash, not bash.
dash doesn't include source, because it's not standard.
Correct your shebang and it'll do the trick.
The standard way to source a script is executing it with ..
Instead of source ./myScript.sh, you do . ./myScript.sh. They're the same in bash.

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