I need to edit an privileged file using bash on Ubuntu 14.04
This simple command is not working:
sudo echo $someText >> $privilegedFile
I get this error:
Permission denied
I have no idea what is wrong with it.
Thanks.
The shell processes the redirection before it runs sudo, so $privilegedFile is still opened using the current user's permissions.
One workaround is to open the file with a program run by sudo rather than using redirections.
echo "$someText" | sudo tee -a "$privilegedFile"
Another is to start an entirely new shell with sudo and execute the full command in that shell.
sudo sh -c "echo '$someText' >> '$privilegedFile'"
You should try this:
sudo sh -c "echo $text >> $file"
do
sudo chmod u+xrw FILE
and
sudo nano FILE
Don't use echo for editing, try nano, gedit or vi.
Related
I'm executing a command with sudo from bash script, and I'm wondering how to prevent sudo from displaying anything on the screen
echo "mypassword" | sudo -S cp -u /scripts/.bashrc ~/ > /dev/null 2>&1
The result will be an output displaying: [sudo] password for username:
I want to hide that output..
now, before the first comment;
This isn't the safest way, since you're entering your password into the script, but this is strictly internal servers.
Run sudo --help, we can get answer from the parameter list:
-p, --prompt=prompt use the specified password prompt
Then,
echo "mypassword" | sudo -S --prompt="" cp -u /scripts/.bashrc ~/ > /dev/null 2>&1
may do the trick.
I install Pip for a user (not system wide) and I would like to check that pip is installed for that user in my script that I run with sudo: sudo ./script.sh
I know to check for a command with command -v pip3 and that works when I enter it in the shell as the user.
But how can I check it in my script?
command -v pip3 exit code is 1 because I am root (because of sudo).
su -c "command -v pip3" "$SUDO_USER" has exit code 1.
sudo -u "$SUDO_USER" command -v pip3 says "command: command not found"
The simplest is
sudo -u "$SUDO_USER" -i command -v pip3
The -i option causes sudo to pass the supplied command line to the user's configured shell using its -c option, instead of trying to execute the command directly. That's necessary because command is a shell built-in; it doesn't exist as a stand-alone executable. (The -i options runs a "login" shell. There is also the -s option which runs a non-login shell. See below.)
If you want to specify a shell explicitly you could do so instead:
sudo -u "$SUDO_USER" /bin/sh -lc "command -v pip3"
Again, a login shell is forced, here by using the -l option.
As a safety feature, sudo normally resets the $PATH to a "safe" value before executing the shell (or the single command). That value will not have any of the modifications made in the /etc/profile and ~/.profile startup scripts, and without those modifications -- which add one or more user-specific directories to the path -- the shell will not find software such as pip3 which has been installed for individual users.
use following command by replacing $USER with the specific user name.
sudo -H -u $USER bash -c 'command -v pip3'
similarly, you can run any command as another user
syntax : sudo -H -u $USER bash -c 'INSERT_COMMAND_HERE'
This question already has answers here:
sudo echo "something" >> /etc/privilegedFile doesn't work [duplicate]
(15 answers)
Closed 5 years ago.
I'm trying to create and fill a file in a directory that requires sudo permission.
EDIT:
It seems that based on tested the suggested similar post.
sudo su -c "echo 'put in file' > file_name"
echo "Some text" | sudo tee /etc/file
will both create a file within the directory that requires sudo permission
The question has been edited to include a log of the problem being introduced, which includes the command:
# Taken from edited question
$ echo 'hello' > sudo tee /data/hello
In bash (which allows redirection operators at any point in a simple command), this is precisely equivalent to running:
# From question, with redirection moved to end to make actual behavior more readable
echo 'hello' tee /data/hello > sudo
That is, it's creating a file named sudo in your current directory, not using sudo to run tee (in the above, tee is just an argument to echo).
What you want, by contrast, is:
# CORRECT: Using a pipe, not a redirection
echo 'hello' | sudo tee /data/hello
with a pipe (|) rather than a >.
Assuming you have the required sudo privileges you could use an editor like vi or nano
sudo vi /etc/file
or
sudo nano /etc/file
If you don't have sudo for those programs you can su to root first and then try:
sudo su -
vi /etc/file
or
nano /etc/file
If you want to do it all on one command line, you can make sure that the file exists by running touch(1) on it. E.g.
sudo touch /etc/file && echo "Some text" | sudo tee /etc/file
I am trying to update the crontab file of 1000+ systems using a for loop from jump host.
The below doesn't work.
echo -e 'pass365\!\n' | sudo -S echo 'hello' >> /var/spool/cron/root
-bash: /var/spool/cron/root: Permission denied
I do have (ALL) ALL in the sudoers file.
This is another solution;
echo 'pass365\!' | sudo -S bash -c 'echo "hello">> /var/spool/cron/root'
The below worked for me.
echo 'pass365\!' | sudo -S echo 'hello' | sudo -S tee -a /var/spool/cron/root > /dev/null
Problem 1: You are trying to send the password via echo to sudo.
Problem 2: You can't use shell redirection in a sudo command like that.
Between the two of these, consider setting up ssh public key authorization and doing
ssh root#host "echo 'hello' \>\> /var/spool/cron/root"
You may eventually get sudo working but it will be so much more pain than this.
I am trying to write a script that appends a line to the /etc/hosts, which means I need sudoer privileges. However, if I run the script from the desktop it does not prompt for a password. I simply get permission denied.
Example script:
#!/bin/bash
sudo echo '131.253.13.32 www.google.com' >> /etc/hosts
dscacheutil -flushcache
A terminal pops up and says permission denied, but never actually prompts for the sudo password. Is there a way to fix this?
sudo doesn't apply to the redirection operator. You can use either echo | sudo tee -a or sudo bash -c 'echo >>':
echo 131.253.13.32 www.google.com | sudo tee -a /etc/hosts
sudo bash -c 'echo 131.253.13.32 www.google.com >> /etc/hosts'
What you are doing here is effectively:
Switch to root, and run echo
Switch back to yourself and try to append the output of sudo onto
/etc/hosts
That doesn't work because you need to be root when you're appending to /etc/hosts, not when you're running echo.
The simplest way to do this is
sudo bash -c "sudo echo '131.253.13.32 www.google.com' >> /etc/hosts"
which will run bash itself as root. However, that's not particularly safe, since you're now invoking a shell as root, which could potentially do lots of nasty stuff (in particular, it will execute the contents of the file whose name is in the environment variable BASH_ENV, if there is one. So you might prefer to do this a bit more cautiously:
sudo env -i bash -c "sudo echo '131.253.13.32 www.google.com' >> /etc/hosts"