Say I have a file at the URL http://mywebsite.example/myscript.txt that contains a script:
#!/bin/bash
echo "Hello, world!"
read -p "What is your name? " name
echo "Hello, ${name}!"
And I'd like to run this script without first saving it to a file. How do I do this?
Now, I've seen the syntax:
bash < <(curl -s http://mywebsite.example/myscript.txt)
But this doesn't seem to work like it would if I saved to a file and then executed. For example readline doesn't work, and the output is just:
$ bash < <(curl -s http://mywebsite.example/myscript.txt)
Hello, world!
Similarly, I've tried:
curl -s http://mywebsite.example/myscript.txt | bash -s --
With the same results.
Originally I had a solution like:
timestamp=`date +%Y%m%d%H%M%S`
curl -s http://mywebsite.example/myscript.txt -o /tmp/.myscript.${timestamp}.tmp
bash /tmp/.myscript.${timestamp}.tmp
rm -f /tmp/.myscript.${timestamp}.tmp
But this seems sloppy, and I'd like a more elegant solution.
I'm aware of the security issues regarding running a shell script from a URL, but let's ignore all of that for right now.
source <(curl -s http://mywebsite.example/myscript.txt)
ought to do it. Alternately, leave off the initial redirection on yours, which is redirecting standard input; bash takes a filename to execute just fine without redirection, and <(command) syntax provides a path.
bash <(curl -s http://mywebsite.example/myscript.txt)
It may be clearer if you look at the output of echo <(cat /dev/null)
This is the way to execute remote script with passing to it some arguments (arg1 arg2):
curl -s http://server/path/script.sh | bash /dev/stdin arg1 arg2
For bash, Bourne shell and fish:
curl -s http://server/path/script.sh | bash -s arg1 arg2
Flag "-s" makes shell read from stdin.
Use:
curl -s -L URL_TO_SCRIPT_HERE | bash
For example:
curl -s -L http://bitly/10hA8iC | bash
Using wget, which is usually part of default system installation:
bash <(wget -qO- http://mywebsite.example/myscript.txt)
You can also do this:
wget -O - https://raw.github.com/luismartingil/commands/master/101_remote2local_wireshark.sh | bash
The best way to do it is
curl http://domain/path/to/script.sh | bash -s arg1 arg2
which is a slight change of answer by #user77115
You can use curl and send it to bash like this:
bash <(curl -s http://mywebsite.example/myscript.txt)
I often using the following is enough
curl -s http://mywebsite.example/myscript.txt | sh
But in a old system( kernel2.4 ), it encounter problems, and do the following can solve it, I tried many others, only the following works
curl -s http://mywebsite.example/myscript.txt -o a.sh && sh a.sh && rm -f a.sh
Examples
$ curl -s someurl | sh
Starting to insert crontab
sh: _name}.sh: command not found
sh: line 208: syntax error near unexpected token `then'
sh: line 208: ` -eq 0 ]]; then'
$
The problem may cause by network slow, or bash version too old that can't handle network slow gracefully
However, the following solves the problem
$ curl -s someurl -o a.sh && sh a.sh && rm -f a.sh
Starting to insert crontab
Insert crontab entry is ok.
Insert crontab is done.
okay
$
Also:
curl -sL https://.... | sudo bash -
Just combining amra and user77115's answers:
wget -qO- https://raw.githubusercontent.com/lingtalfi/TheScientist/master/_bb_autoload/bbstart.sh | bash -s -- -v -v
It executes the bbstart.sh distant script passing it the -v -v options.
Is some unattended scripts I use the following command:
sh -c "$(curl -fsSL <URL>)"
I recommend to avoid executing scripts directly from URLs. You should be sure the URL is safe and check the content of the script before executing, you can use a SHA256 checksum to validate the file before executing.
instead of executing the script directly, first download it and then execute
SOURCE='https://gist.githubusercontent.com/cci-emciftci/123123/raw/123123/sample.sh'
curl $SOURCE -o ./my_sample.sh
chmod +x my_sample.sh
./my_sample.sh
This way is good and conventional:
17:04:59#itqx|~
qx>source <(curl -Ls http://192.168.80.154/cent74/just4Test) Lord Jesus Loves YOU
Remote script test...
Param size: 4
---------
17:19:31#node7|/var/www/html/cent74
arch>cat just4Test
echo Remote script test...
echo Param size: $#
If you want the script run using the current shell, regardless of what it is, use:
${SHELL:-sh} -c "$(wget -qO - http://mywebsite.example/myscript.txt)"
if you have wget, or:
${SHELL:-sh} -c "$(curl -Ls http://mywebsite.example/myscript.txt)"
if you have curl.
This command will still work if the script is interactive, i.e., it asks the user for input.
Note: OpenWRT has a wget clone but not curl, by default.
bash | curl http://your.url.here/script.txt
actual example:
juan#juan-MS-7808:~$ bash | curl https://raw.githubusercontent.com/JPHACKER2k18/markwe/master/testapp.sh
Oh, wow im alive
juan#juan-MS-7808:~$
command to redirect output to console and to a file at the same time works fine in bash. But how do i make it work in korn shell(ksh).
All my scripts runs on korn shell so cant change them to bash for this particular command to work.
exec > >(tee -a $LOGFILE) 2>&1
In the code beneath I use the variable logfile, lowercase is better.
You can try something like
touch "${logfile}"
tail -f "${logfile}"&
tailpid=$!
trap 'kill -9 ${tailpid}' EXIT INT TERM
exec 1>"${logfile}" 2>&1
A not too unreasonable technique is to re-exec the shell with output to tee. That is, at the top of the script, do something like:
#!/bin/sh
test -z "$REXEC" && { REXEC=1 exec "$0" "$#" | tee -a $LOGFILE; exit; }
How can I run nested shell scripts with the same option? For example,
parent.sh
#!/bin/sh
./child.sh
child.sh
#!/bin/sh
ls
How can I modify parent.sh so that when I run it with sh -x parent.sh, the -x option is effective in child.sh as well and the execution of ls is displayed on my console?
I'm looking for a portable solution which is effective for rare situations such as system users with /bin/false as their registered shell. Will the $SHELL environment variable be of any help?
Clarification: I sometimes want to call parent.sh with -x, sometimes with -e, depending on the situation. So the solution must not involve hard-coding the flags.
If you use bash, i can recommend the following:
#!/bin/bash
export SHELLOPTS
./child.sh
You can propagate as many times as you need, also you can use echo $SHELLOPTS in every script down the line to see what is happening and how options are propagated if you need to understand it better.
But for /bin/sh it will fail with /bin/sh: SHELLOPTS: readonly variable because of how POSIX is enforced on /bin/sh in various systems, more info here: https://lists.gnu.org/archive/html/bug-bash/2011-10/msg00052.html
it's looks like a hack and seems it's not the best way.
But it will do exact what you want
One of the ways how you can do it - it's to create aliases to create wrappers for sh:
alias saveShell='cp /bin/sh $some_safe_place'
alias shx='cp $some_safe_place /bin/x_sh; rm /bin/sh; echo "/bin/x_sh -x $#" > /bin/sh; chmod 755 /bin/sh '
alias she='cp $some_safe_place /bin/e_sh; rm /bin/sh; echo "/bin/e_sh -e $#" > /bin/sh; chmod 755 /bin/sh '
alias restoreShell='cp $some_safe_place /bin/sh'
How to Use:
run saveShell and then use shx or she , if you would change -x on -e run restoreShell and then run shx or she
run script as usually
sh ./parent.sh
BE VERY CAREFUL WITH MOVING SH
Other solution
replace #!/bin/sh to #!/bin/sh -x or #!/bin/sh -e with sed in all sh files before running script.
Regardless of why, I am trying to write a script that will let me send a command to various addresses. There is a shared key for the user, so there is no need for logging in. But this isn't working.
So, the following will not work...
#!/bin/bash
ip=$1
shift
args="'$#'"
cmd="ssh user#$ip -C $args"
output=$($cmd)
If I execute it with the following:
./myscript.sh 10.0.1.2 /bin/ls -l /var
I get the error of "ls -l /var: No such file or directory"
If I run that command (ssh user#10.0.1.2 -C '/bin/ls -l /var'), it works fine.
What am I doing wrong? These are the same installs of RHEL6.
Apparently, the quotes were confusing bash. The following works...
ip=$1
shift
$(ssh -o ConnectTimeout=1 User#$ip "$#")
Consider the following shell script on example.com
#/bin/bash
export HELLO_SCOPE=WORLD
eval $#
Now, I would like to download and then execute this shell script with parameters in the simplest way and be able to launch an interactive bash terminal with the HELLO_SCOPE variable set.
I have tried
curl http://example.com/hello_scope.sh | bash -s bash -i
But it quits the shell immediately. From what I can understand, it's because curls stdout, the script, remains the stdin of the bash, preventing it from starting interactively (as that would require my keyboard to be stdin).
Is there a way to avoid this without going through the extra step of creating a temporary file with the shell script?
You can source it:
# open a shell
. <(curl http://example.com/hello_scope.sh)
# type commands ...
You could just download this script you (using wget for example) and source this script, isn't it ?
script_name="hello_scope.sh"
[[ -f $script_name ]] && rm -rf "$script_name"
wget "http://example.com/$script_name" -O "$script_name" -o /dev/null
&& chmod u+x "$script_name"
&& source "$script_name"
You could use . "$script_name" instead of source "$script_name" if you want (. is POSIX compliant). You could write the previous code in a script and source it to have interactive shell with the setted variable $HELLO_SCOPE.
Finally you could remove the eval line in your remote shell script.