cp command from tcl script - linux

Hi I am writing a tcl script to automate the task in linux. In that I want to copy files.
The command is
cp -r source destination. I have tried using
puts [cp -rf source destination]. But I am getting error saying invalid command cp. How will I write it in tcl script.

To run an external program from your script, you should use the exec command:
puts [exec cp -r $source $destination]
However, for the specific case of copying a directory from one place to another you can use the built-in file copy command (which works with directories as well as files):
file copy $source $destination

Related

Is it possible to create an empty file using scp?

In *nix, I can create an empty file using cp:
cp /dev/null ~/emptyfile
I'd like to know if it's possible to do something similar using scp (instead of ssh + touch). If I try to run:
scp /dev/null remoteserver:~/emptyfile
it returns an error /dev/null: not a regular file
EDIT:
Just to clarify, I don't wanna run any command at the remoteserver (i.e. No ssh command should be invoked).
So it's ok to run some command at localhost (echo, cat, dd or any other trivial command) and copy the resulting file to remoteserver.
It's preferable not leaving the resulting file at localhost. It's also good if the resulting command is an one-liner solution.
EDIT2:
It's impossible to use /dev/null approach as in cp command, because scp only works with regular files and directories:
https://github.com/openssh/openssh-portable/blob/8a85f5458d1c802471ca899c97f89946f6666e61/scp.c#L838-L850
So it's mandatory to use another command (touch, cat, dd etc) to create a regular empty file (either in a previous command, pipe or a subshell).
As #willh99 commented, creating an empty file locally, and then performing scp is the most feasible solution.
So far I came up with this:
filename=$(mktemp) && scp $filename remoteserver:~/emptyfile; rm $filename
It creates an empty file in a subshell, and copies it to remoteserver as emptyfile.
Any refactor/improvements are welcome.
EDIT: remove $filename whether scp succeeding or not, as stated by #Friek.
If you're just trying to create an empty file, you can use ssh and run the touch command like this:
ssh username#remoteserver touch anemptyfile

Error copying files in Linux shell bash script

I'm try to copy files from a location (/home/ppaa/workspace/partial/medium) to another location (/home/ppaa/workspace/complete) using bash shell scripting in Linux.
This is my code:
#!/bin/bash -u
MY_BASE_FOLDER='/home/ppaa/workspace/'
MY_TARGET_FOLDER='/home/ppaa/workspace/complete/'
cp $MY_BASE_FOLDER'partial/medium/*.*' $MY_TARGET_FOLDER
return=$?
echo "return: $return"
The folders exists and the files are copied but the value of return variable is 1. Whats wrong?
The files are not copied. cp is most likely giving you an error like:
cp: cannot stat ‘/home/ppaa/workspace/partial/medium/*.*’: No such file or directory
This is because globs (like *.*) are not expanded in quotes. Instead, use:
cp "$MY_BASE_FOLDER/partial/medium"/*.* "$MY_TARGET_FOLDER"

Bash script failing to execute bash script

I'm trying to run a script that installs some files in a directory a user specifies. Once the user specifies the directory, I'd like to transfer the main file to that directory so it can perform so more tasks there before ultimately deleting itself once complete.
#prompt for directory in which to build project
read -p "Drag and drop the directory in which you'd like to build this project: "
echo "reply is $REPLY"
cp ./myScript.sh $REPLY
/bin/bash $REPLY/myScript.sh
I've got the script to execute the file from this question. I tried doing it with source $REPLY/myScript.sh as well as simply sh $REPLY/myScript.sh. I get the error /path/to/file/ is a directory
It must be that it doesn't known I'm trying to run myScript.sh, but I don't understand how I've given it a directory.
A likely cause is that drag-and-drop is putting whitespace after the directory name.
Thus:
/bin/bash $REPLY/myScript.sh
would be running
/bin/bash /path/to/directory /myScript.sh
A simple fix, if that's only a standard space, would be:
/bin/bash "${REPLY% }/myScript.sh"
You are missing the variable in read command so obiously it will fail as whatever you are reading is not getting stored. You can replace the read command as follows.
#prompt for directory in which to build project
read -p "Drag and drop the directory in which you'd like to build this project: " REPLY

Recursively copy contents of directory to all target directories

I have a directory containing a set of subdirectories and files. I need to recursively copy all the content of this directory to all the subdirectories of another directory, also recursively.
How do I achieve this, preferably without using a script and only with the cp command?
You can write this in a script but you don't have to. Just write it line by line in the terminal:
# $TARGET is the directory containing subdirectories where you want to STORE the copies
# $SOURCE is the directory containing the subdirectories you want to COPY
for dir in $(ls $TARGET); do
cp -r $SOURCE/* $TARGET/$dir
done
Only uses cp and runs on both bash and zsh.
You can't. cp can copy multiple sources but will only copy to a single destination. You need to arrange to invoke cp multiple times - once per destination - for what you want to do; using, as you say, a loop or some other tool.
The first part of the command before the pipe instruct tar to create an archive of everything in the current directory and write it to standard output (the – in place of a file-name frequently indicates stdout).
tar cf - * | ( cd /target; tar xfp -)
The commands within parentheses cause the shell to change directory to the target directory and untar data from standard input. Since the cd and tar commands are contained within parentheses, their actions are performed together.
The -p option in the tar extraction command directs tar to preserve permission and ownership information, if possible given the user executing the command. If you are running the command as superuser, this option is turned on by default and can be omitted.
Also you can use the following command, but it seems to be quite slower than tar;
cp -a * /target

simple shell script to copy files and folders and also execute a command

I haven't written any Shell scripts before, but i have to write a simple shell script to do the following;
I will keep all the required files in a single folder and bundle it with this shell script as a tar file; so when the user runs the shell script, it needs to copy the respective files to the respective destinations.
The execution of copy as follows:
copy the plugin.so file to /usrlib/mozilla/plugins/
copy the .so library files to /usr/local/lib/
copy some header files directories(folders) to /usr/local/include/
and finally, need to do ldconfig.
Basically, you can add in a script any command you are able to type inside the terminal itself. Then, you have two options for executing it:
Execute it from the terminal with sh your_script.sh. You don't even need to give execute permission to it with this solution.
Give it the execute permission and run it with ./your_script.sh.
For the second solution, you have to start the file with what is called a shebang. So your script will look like:
#!/bin/sh
cp path/to/source path/to/destination
cp path/to/source path/to/destination
cp path/to/source path/to/destination
ldconfig
echo "Done!"
Nothing else. Just write the commands one after the other.
The first line is the so-called shebang and tells the shell which interpreter to use for the script.
Note: the extension for shell scripts is usually .sh, but you can actually name your file however you prefer. The extension has no meaning at all.
Good scripting!

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