How to install vncserver with a password? - centos

I am trying to install tigervnc-server from a bash script with a password under Centos 6.
I want to do this because I want to automate VPS installations. Does anybody know how to do this? Tried adding two lines in the script with the password because it requires you to enter a password 2 times but it didnt worked, it said command not found and I didnt got past it. Thanks for the help!

#!/bin/bash
# Options:
PASSWORD="mysecret"
DISPLAY=":10"
VNCSERVER_OPTIONS="-geometry 1024x768 -alwaysshared"
PASSWD_PATH="$HOME/.vnc/passwd"
XSTARTUP_PATH="$HOME/.vnc/xstartup"
VNCSERVER="tightvncserver"
VNCPASSWD="tightvncpasswd"
# NOTE: you can change `tightvncpasswd` by `vncpasswd` if you don't use
# TightVNC but it won't work in some VNC implementations
NEW_SESSION="exec gnome-session"
vncserver_stop() {
# Kill server for this display if is running
$VNCSERVER -clean -kill $DISPLAY
}
vncserver_start() {
echo "$PASSWORD" | $VNCPASSWD -f > $PASSWD_PATH
chmod 600 $PASSWD_PATH
echo "$NEW_SESSION" > $XSTARTUP_PATH
$VNCSERVER $DISPLAY $VNCSERVER_OPTIONS
}
case "$1" in
start)
vncserver_start
;;
stop)
vncserver_stop
;;
restart)
tightvnc_stop
tightvnc_start
;;
*)
echo "Usage: $0 <start|stop|restart>"
exit 1
esac

Related

skip Helm uninstall interactive request

i want to automate a bit helm install/uninstall but during helm uninstall command it will become user interactiv asking:
Do you want to continue to delete suite-helm? (yY|nN):
Is any flag or way to skip this part?
Thanks in advance
finaly i found a way using expect and here it is:
expect -c ' spawn ./helm_remove.sh; expect (yY|nN); send "y\n"; interact'
into sh file i will have helm uninstall suite-helm -n suite-helm and some other commands to remove pvs deployment...
You would have to wrap in a shell script or function.
Something like (just spitballing here, not even syntax checking)
helm-delete() {
helm status $1
echo "Do you want to continue to delete suite-helm? (yY|nN):"
read -rs -k 1 ans
case "${ans}" in
y|Y|$'\n')
printf "Yes\n"
helm delete %1
;;
*) # This is the default
printf "No\n"
return 0
esac
}

sh script gets stuck on read command in while loop

I'm trying to write a script that I'll put in my pi's cron to check for network connectivity every 10 seconds, if it fails a ping to google it will write a text file as false, then next time it succeeds, it will restart a program, because the specific program has issues with reconnecting to the network automatically.
The script seemed to be working when I was executing it from the terminal out of the same directory, then I cd back to / and added a bunch of comments, and now it just exits the script without any output, and for the life of me I can't figure out where i messed it up - I'm still relatively new to scripting so I could be missing something absolutely obvious here, but I couldn't find anything useful on google.
file heirarchy:
/home/pi/WEB_UI/
inside the WEB_UI folder are both of the scripts i'm running here.
nonet.sh - the script in question
pianobar.sh - a simple script to pkill a program and reload it after 5 seconds.
var.txt - a text file that will only ever contain "true" or "false
I've tried removing all of the comments, changing the file locations to ./ and making the while; do commands a single line, but I can't figure out where the issue is. if I run sh -x for the script, it returns:
pi#raspberrypi:~/WEB_UI $ sh -x nonet.sh
+ ping -q -c 1 -W 1 google.com
+ read line
interestingly I get the same result from a test script I was using that was basically
"if var.txt says 'true', echo 'up', else echo 'down'"
I wonder if something is wrong with my sh interpreter?
#!/bin/sh
#ping google, if successful return true
if ping -q -c 1 -W 1 google.com >/dev/null; then
#read variable line, perform action do
while read line
do
#leading $ means return previous output. if line is false:
if [ "$line" = "false" ]
then
#return network up text, run pianobar script, set var.txt to true.
echo "the network is back up"
sh /home/pi/WEB_UI/pianobar.sh
echo true > /home/pi/WEB_UI/var.txt
else
#otherwise return network is up, set var.txt to true
echo "the network is up"
echo true > /home/pi/WEB_UI/var.txt
#fi ends an if statement, done ends a while loop.
#text after done tells the while loop where to get the line variable
fi
done < /home/pi/WEB_UI/var.txt
else
while read line
do
if [ "$line" = "false" ]
then
#if var.txt is already false, ping google again
if ping -q -c 1 -W 1 google.com >/dev/null; then
#if ping works, the network is back, restart pianobar, set var to true
echo "the network is back up"
sh /home/pi/WEB_UI/pianobar.sh
echo true > /home/pi/WEB_UI/var.txt
else
#if var.txt is false, network is still down. wait.
echo "the network is still down"
fi
else
echo "the network is down"
echo false > /home/pi/WEB_UI/var.txt
fi
done < /home/pi/WEB_UI/var.txt
fi
the script SHOULD just echo a simple line saying whether the network is up, down, back up, or still down, depending on how many flags it passes/fails. Any assistance would be greatly appreciated!
as Shellter said in comments above, the issue was that I needed to add \n to the end of the line in my var.txt
I think I saw another post recently where while read... was frustrated by a missing \n char, so maybe you want to do printf "false\n" > file instead. Good luck.

How can I make a function run every time cd successfully changes to another directory within sh on FreeBSD?

I'm using sh as my shell on FreeBSD but I want to be able to have a pretty prompt like the one bash gives me on Ubuntu. There are two things that the FreeBSD implementation of sh seems to lack as far as PS1 escape characters go:
The \w works but does not expand $HOME to ~, so this is something I have already hacked up myself
I can use PS1 to update the prompt on the terminal, but as far as I can tell it is not possible to use the PS1 variable to update the title bar as well. ESC and BEL fail to set the title as one would expect if they were using bash or ksh
Here is my .shrc file
update_prompt() {
case "$PWD" in
"$HOME"*)
pretty_pwd="~${PWD#*"${HOME}"}"
;;
"/usr$HOME"*)
pretty_pwd="~${PWD#*"/usr${HOME}"}"
;;
*)
pretty_pwd="$PWD"
;;
esac
case "$TERM" in
xterm*|rxvt*)
PS1="[$USER#\\h $pretty_pwd]\\$ "
;;
*)
;;
esac
printf "\\033]0;[%s#$(hostname -s): %s]\\007" "$USER" "$pretty_pwd"
}
update_prompt
So when I fire up a terminal or log in via ssh, it gives the pretty prompt that I like. But now I need this function to run every time that cd is executed and returns an exit status of 0.
I was going to use an alias that was something like:
alias cd="cd $1 && update_prompt"
but that was before I realized that aliases do not except arguments. How might I go about doing something like this?
You can use a function instead of an alias:
cd() {
command cd "$#" && update_prompt
}
Just put it into ~/.shrc. You have to use command here to let sh know that you are referring to the actual cd builtin command instead of the function you've just defined.
Refer to the sh(1) manual page for the details on how to make sh(1) source the ~/.shrc file when it starts:
Therefore, a user should place commands that are to be executed only at login
time in the .profile file, and commands that are executed for every shell
inside the ENV file. The user can set the ENV variable to some file by placing
the following line in the file .profile in the home directory, substituting for
.shrc the filename desired:
ENV=$HOME/.shrc; export ENV
I use this trick in my cd alias manager. Here's a link to the source code of the function: https://github.com/0mp/goat/blob/v2.5.0/libgoat.sh#L31-L57
You can do it with alias+arguments if you swap the commands:
$ alias cd="echo change; cd"
$ pwd
/nas
$ cd /
change
$ pwd
/
$ cd /etc
change
$ pwd
/etc
$

Including some SFTP commands in a Makefile

I use a Makefile to create pdfs of papers I'm working on. I'd also like to use make to upload the latest version to my website, which requires sftp. I though I could do something like this (which words on the command line) but it seems that in make, the EOF is getting ignored i.e., this
website:
sftp -oPort=2222 me#mywebsite.com << EOF
cd papers
put research_paper.pdf
EOF
generates an error message
cd papers
/bin/sh: line 0: cd: papers: No such file or directory
which I think is saying "papers" doesn't exist on your local machine i.e., the 'cd' is being executed locally, not remotely.
Couple of ideas:
use ncftp which every Linux distro as well as brew should have: it remembers 'state' so the cd becomes unnecessary
use scp instead of sftp if possible
write a trivial shell script doing the EOF business and call that
For what it is worth, here is my script to push tarballs to the CRAN winbuilder -- and takes target directory and script as arguments to ncftpput.
#!/bin/bash
function errorexit () {
echo "Error: $1"
exit 1
}
if [ "$#" -lt 1 ]; then
errorexit "Need to specify argument file"
fi
if [ ! -f ${1} ]; then
errorexit "File ${1} not found, aborting."
fi
ncftpput win-builder.r-project.org /R-release ${1}
ncftpput win-builder.r-project.org /R-devel ${1}
I then just do wbput.sh foo_1.2-3.tar.gz and off it goes...
You cannot (normally) put a single command on multiple lines in a Make recipe, so here documents are a no-go. Try this instead:
website: research_paper.pdf
printf 'cd papers\nput $<\n' \
| sftp -oPort=2222 me#mywebsite.com
The target obviously depends on the PDF, so I made it an explicit dependency, as well.

MacVim: create new file from command line by using `alias mvim="open -a macvim"`

When I use vim newfilename to open a file and this file does not exit, vim will create a new file with the name newfilename.
However, MacVim does not work in this way --- i.e. mvim newfilename (alias mvim="open -a macvim") will lead to an error: newfilename does not exist
Is there a way to configure MacVim such that mvim newfilename (alias mvim="open -a macvim") will create a new file and open it?
I'm guessing the error message comes from open, not from vim. You can replace your alias with a function;
mvim () {
local f
for f; do
test -e "$f" || touch "$f"
done
open -a macvim "$#"
}
This will create empty files if necessary before opening them.
edit Didn't see #Peter Lyons' comment about this; credit should go to him for first suggesting this solution. I'll be happy to remove this answer if Peter wants to submit his.
You don't need the mvim alias to the open command, you can instead use the mvim launcher script that comes bundled with most MacVim Snaphots. After adding that mvim to your path, then runing mvim newfile, will now open a newfile buffer in an new MacVim window just like gvim would.
The MacVim mvim script as linked to above:
#!/bin/sh
#
# This shell script passes all its arguments to the binary inside the
# MacVim.app application bundle. If you make links to this script as view,
# gvim, etc., then it will peek at the name used to call it and set options
# appropriately.
#
# Based on a script by Wout Mertens and suggestions from Laurent Bihanic. This
# version is the fault of Benji Fisher, 16 May 2005 (with modifications by Nico
# Weber and Bjorn Winckler, Aug 13 2007).
# First, check "All the Usual Suspects" for the location of the Vim.app bundle.
# You can short-circuit this by setting the VIM_APP_DIR environment variable
# or by un-commenting and editing the following line:
# VIM_APP_DIR=/Applications
if [ -z "$VIM_APP_DIR" ]
then
myDir="`dirname "$0"`"
myAppDir="$myDir/../Applications"
for i in ~/Applications ~/Applications/vim $myDir $myDir/vim $myAppDir $myAppDir/vim /Applications /Applications/vim /Applications/Utilities /Applications/Utilities/vim; do
if [ -x "$i/MacVim.app" ]; then
VIM_APP_DIR="$i"
break
fi
done
fi
if [ -z "$VIM_APP_DIR" ]
then
echo "Sorry, cannot find MacVim.app. Try setting the VIM_APP_DIR environment variable to the directory containing MacVim.app."
exit 1
fi
binary="$VIM_APP_DIR/MacVim.app/Contents/MacOS/Vim"
# Next, peek at the name used to invoke this script, and set options
# accordingly.
name="`basename "$0"`"
gui=
opts=
# GUI mode, implies forking
case "$name" in m*|g*|rm*|rg*) gui=true ;; esac
# Restricted mode
case "$name" in r*) opts="$opts -Z";; esac
# vimdiff, view, and ex mode
case "$name" in
*vimdiff)
opts="$opts -dO"
;;
*view)
opts="$opts -R"
;;
*ex)
opts="$opts -e"
;;
esac
# Last step: fire up vim.
# The program should fork by default when started in GUI mode, but it does
# not; we work around this when this script is invoked as "gvim" or "rgview"
# etc., but not when it is invoked as "vim -g".
if [ "$gui" ]; then
# Note: this isn't perfect, because any error output goes to the
# terminal instead of the console log.
# But if you use open instead, you will need to fully qualify the
# path names for any filenames you specify, which is hard.
exec "$binary" -g $opts ${1:+"$#"}
else
exec "$binary" $opts ${1:+"$#"}
fi