I am trying to create a patch that users can use to remotely edit a file in a pre-defined way using sed, and I could do this manually on each computer, but it would take a long time.
The line I am struggling with is as follows:
host=[hostname]
port=[portnum]
ssh -t $host -p $port "cp ~/file1 ~/file1.bak ; sed -i \"s/fcn1('param1', $2)\n/fcn2('param2'):$zoom\n/g\" ~/file1"
This makes a backup of file1 and then edits a line in the file. I actually want to edit more than one line, but this line demonstrates the problems:
The command works, provided no $ signs are used within the sed command.
I have tried a number of ways of escaping these $ signs but cannot seem to find one that works.
I can use a . wildcard in the find, but obviously not in the replace string.
I would use single quotes for the sed command, in order to avoid expanding the $2, but single quotes are already used inside the command.
Does anyone have any ideas of how to overcome this problem? Thanks in advance for any suggestions!
This should work as well:
ssh -t $host -p $port "cp ~/file1 ~/file1.bak && sed -i \"s/fcn1('param1', \\\$2)/fcn2('param2'):\\\$zoom/g\" file1"
You need 3 back slashes as you have to escape the $ sign in the string passed in the remote bash to sed. And you have to escape that back slash and the $ sign when sending it over via ssh.
Related
I'm looking to search some files via SSH with the grep command but I have some special chars.
The string I'm looking for is:
"$GLOBALS['....'];"
I tried this one
grep -r -H "\$GLOBALS\\['*'\\]\;" /var/www/
but nothing happens. Any help will be welcome.
Your RE actually matches "$GLOBALS['''''''];" with one or more ' there.
try this one:
grep -rHP "[$]GLOBALS\['.*?']\;" file
I use [$] instead of \$, is because ESCAPE IS SOMEHOW TRICKY, some environment you need use \\\$.
Update, less than 10 chars inside the []:
grep -rHP "[$]GLOBALS\['.{0,10}']\;" file
I am trying to do something like this inside ssh session:
Script
ssh remoteservername "
col=`sed -n "8p" /tmp/temp.txt`
echo $col>>/tmp/Ankur.txt
"
This is not working and it is printing empty line instead of text what I want to store in col variable, why so, and this is working:
ssh remoteservername "
sed -n "8p" /tmp/temp.txt>>/tmp/Ankur.txt
"
This Ankur.txt file is on the remote server....The main focus is how to get the output of the command inside a variable so that i can use it further.
Please tell how to make it work.
Thanks
When you use double quotes the variable names will get expanded before passing them, so $col is getting expanded locally before running on the remote server. You can either escape the $ like \$col or use single quotes around it, which is probably better since you want to use double quotes inside the command as well
ssh remoteservername '
col=`sed -n "8p" /tmp/temp.txt`
echo $col>>/tmp/Ankur.txt
'
Without changing the quotes
ssh remoteservername 'sed -n "8p" /tmp/temp.txt >> /tmp/Ankur.txt'
as you noted, still works, by redirecting the output directly into the file. This avoids the variable expansion problem from the double quotes above.
If you're going to have many steps though, you might want to just create a script on remoteservername and invoke that in your ssh command rather than doing a lot on the same command line.
You can use a local file to execute complex commands and to use variables in remote machine via SSH as shown below.
1. Create a input file 'input_file.txt'
#-- input_file.txt
col=`sed -n "8p" /tmp/temp.txt`
echo $col>>/tmp/Ankur.txt
2. Execute the commands of input file in remote server via SSH
ssh remoteservername "sh -s" < input_file.txt
I'm trying to automate a script that copies a file from my local server to a remote server on the command line. I've done the research on scp and know how to copy the file to the remote server, but then I want to append that file to another.
This is my code:
scp ~/file.txt user#host:
ssh user#host cat file.txt >> other_file.txt
When I enter everything into the command line manually as such, everything works fine:
scp ~/file.txt user#host:
ssh user#host
cat file.txt >> other_file.txt
But when I run the script, only the file is copied, not appended to the end of other_file.txt. Help?
The second line of your code should be
ssh user#host "cat file.txt >> other_file.txt"
Three important points:
You don't want your local shell to interpret >> in any way (which it does if it's unquoted)
There is a remote shell which will interpret >> in the command correctly.
Final arguments to ssh are "joined" to form a command, not carried into an argv array as they are. It may be convenient but it also may lead to confusion or bugs: ssh cat "$MYFILE" and ssh "cat '$MYFILE'" both work in a common use case, but they both break for different values of $MYFILE.
You need to enclose the command to be run on the remote host in quotes. Otherwise, the redirection is being done locally rather than remotely. Try this instead:
scp ~/file.txt user#host:
ssh user#host 'cat file.txt >> other_file.txt'
Try this:
$ cat file.txt| ssh hostname 'cat >> other_file.txt'
I'm trying to write several commands trought ssh connection bue I got problem with escape characters. Below an example of what I'd like to do:
/usr/bin/ssh mrtg#172.20.29.40 echo -e "ciao\nprova"
I got this result:
ciaonprova
instead of:
ciao
prova
if I use -e option for ssh:
/usr/bin/ssh -e mrtg#172.20.29.40 echo -e 'ciao\nprova'
I receive this error:
Bad escape character 'mrtg#172.20.29.40'.
Can someone give me a suggestion to let remote server interpret escape characters?
The -e option has nothing to do with your command (these are SSH escape characters, not shell).
You can just put your command in quotes:
/usr/bin/ssh mrtg#172.20.29.40 'echo -e "ciao\nprova"'
I have foo.sql as:
print 'foo=$(foo)'
Then I have in foo.cmd the following shell script:
sqlcmd -i foo.sql -v foo="c:\path"
Running foo.cmd prints:
foo=\path
how do I escape the "c:"? Is dos-shell eating it, or is it sqlcmd?
cmd's argument delimiters include the equal sign. I've seen in other cases (such as bjam.exe) that the entire parameter sequence has to be quoted to work properly.
Try this:
sqlcmd -i foo.sql -v "foo=c:\path"
If it still strips the "c:" portion, I'd focus on sqlcmd. I don't personally have it installed to test with. This is based solely on experience with similar situations.
OK, my mistake. the above does work.
What i did wrong was doing: sqlcmd -i foo.sql -v foo='c:\path'
(single quote, since I tried to pass them as ' ' sql string) that won't work. it will chop the c:
Using another shell causes this.
I just had this when running sqlcmd via powershell. Switched to using cmd.exe and it worked fine
double quotes to escape the ":" and single quotes so that sql treated the variable value as a string. e.g.
sqlcmd -S . -d myDb -i .\test.sql -v pathToFile = "'D:\Temp\temp\My.csv'"
Escape the backslash,
sqlcmd -i foo.sql -v foo="c:\\path"
It's actually your shell eating the \