Making a bash script, and I am trying to figure out a way to find out what my symbolic link points to. Right now, I am doing it with this, but this only works if my symlink is in the current directory. Is there a way to find out what my symlink is pointing to if it is in another directory?
ls -l "symlink" | cut -d'>' -f2
If you have the readlink(1) utility (part of GNU coreutils), it does what you want. Otherwise you are kinda up a creek, I'm not aware of any straightforward & portable equivalent.
On a BSD toolchain, I am doing:
stat -f %Y <filename>
For example:
% ln -sf /bsd ~/blah
% stat -f %Y ~/blah
/bsd
On a GNU toolchain it is not so easy, you can use something like:
$ stat -c %N /usr/bin/firefox
`/usr/bin/firefox' -> `../lib/firefox-3.6.12/firefox.sh'
Then, use awk/cut and sed to extract and remove junk quotes.
Or a messier solution is to use ls -al and either awk/cut to extract the column you need.
Related
I have a directory full of files with names such as:
file_name_is_001
file_name_001
file_name_is_002
file_name_002
file_name_is_003
file_name_003
I want to copy only the files that don't contain 'is'. I'm not sure how to do this. I have tried to search for it, but can't seem to google the right phrase to find the results.
Details depend on operating system, shell, etc.
For a unix system a quite verbose but easy to understand approach could look like this (please mind that I didn't test it):
mkdir some_temporary_directory
mv *_is_* some_temporary_directory
cp * where_ever_you_want_to_copy_it
mv some_temporary_directory/* .
rmdir some_temporary_directory
You can do this using bash. First, here's a command to get you a list of files that don't contain the text _is_:
ls | grep -v "_is_"
This takes the output of ls and matches all values with DO NOT contain _is_ using grep -v.
In order to then copy these files, we need to turn the lines output by grep into arguments of cp. We can do this using xargs:
ls | grep -v "_is_" | xargs -J % cp % new_folder
From the xargs man page, it is a tool to "build and execute command lines from standard input".
Hi this is a simple question but the solution eludes me at the moment..
I can find out the folder name that I want to change the name of, and I know the command to change the name of a folder is mv
so from the current directory if i go
ls ~/relevant.directory.containing.directory.name.i.want.to.change
to which i get the name of the directory is called say lorem-ipsum-v1-3
but the directory name may change in the future but it is the only directory in the directory:
~/relevant.directory.containing.directory.name.i.want.to.change
how to i programmatically change it to a specific name like correct-files
i can do it normally by just doing something like
mv lorem-ipsum-v1-3 correct-files
but I want to start automating this so that I don't need to keep copying and pasting the directory name....
any help would be appreciated...
Something like:
find . -depth -maxdepth 1 -type d | head -n 1 | xargs -I '{}' mv '{}' correct-files
should work fine as long as only one directory should be moved.
If you are absolutely certain that relevant.directory.containing.directory.name.i.want.to.change only contains the directory you want to rename, then you can simply use a wildcard:
mv ~/relevant.directory.containing.directory.name.i.want.to.change/*/ ~/relevant.directory.containing.directory.name.i.want.to.change/correct-files
This can can also be simplified further, using bash brace expansion, to:
mv ~/relevant.directory.containing.directory.name.i.want.to.change/{*/,correct-files}
cd ~/relevant.directory.containing.directory.name.i.want.to.change
find . -type d -print | while read a ;
do
mv $a correct-files ;
done
Caveats:
No error handling
There may be a way of reversing the parameters to mv so you can use xargs instead of a while loop, but that's not standard (as far as I'm aware)
Not parameterised
If there any any subdirectories it won't work. The depth parameters on the find command are (again, AFAIK) not standard. They do exist on GNU versions but seem to be missing on Solaris
Probably others...
Basically we need to change the end of line characters for a group of files.
Is there a way to accomplish this with a batch file? Is there a freeware utility?
dos2unix
It could be done with somewhat shorter command.
find ./ -type f | xargs -I {} dos2unix {}
You should be able to use tr in combination with xargs to do this.
On the Unix side at least, this should be the simplest way. However, I tried doing it that way once on a Windows box over a decade ago, but discovered that the Windows version of tr was translating my terminators right back to Windows format for me. :-( However, I think in the interveneing decade the tools have gotten smarter.
Combine find with dos2unix/fromdos to convert a directory of files (excluding binary files).
Just add this to your .bashrc:
DOS2UNIX=$(which fromdos || which dos2unix) \
|| echo "*** Please install fromdos or dos2unix"
function finddos2unix {
# Usage: finddos2unix Directory
find $1 -type f -exec file {} \; | grep " text" | cut -d ':' -f1 | xargs $DOS2UNIX
}
First, DOS2UNIX finds whether you have the utility installed, and picks one to use
Find makes a list of all files, then file appends the ": ASCII text" after each text file.
Finally, grep picks the text files, Cut removes all text after ':', and xargs makes this one big command line for DOS2UNIX.
I have two directories with the same list of files. I need to compare all the files present in both the directories using the diff command. Is there a simple command line option to do it, or do I have to write a shell script to get the file listing and then iterate through them?
You can use the diff command for that:
diff -bur folder1/ folder2/
This will output a recursive diff that ignore spaces, with a unified context:
b flag means ignoring whitespace
u flag means a unified context (3 lines before and after)
r flag means recursive
If you are only interested to see the files that differ, you may use:
diff -qr dir_one dir_two | sort
Option "q" will only show the files that differ but not the content that differ, and "sort" will arrange the output alphabetically.
Diff has an option -r which is meant to do just that.
diff -r dir1 dir2
diff can not only compare two files, it can, by using the -r option, walk entire directory trees, recursively checking differences between subdirectories and files that occur at comparable points in each tree.
$ man diff
...
-r --recursive
Recursively compare any subdirectories found.
...
Another nice option is the über-diff-tool diffoscope:
$ diffoscope a b
It can also emit diffs as JSON, html, markdown, ...
If you specifically don't want to compare contents of files and only check which one are not present in both of the directories, you can compare lists of files, generated by another command.
diff <(find DIR1 -printf '%P\n' | sort) <(find DIR2 -printf '%P\n' | sort) | grep '^[<>]'
-printf '%P\n' tells find to not prefix output paths with the root directory.
I've also added sort to make sure the order of files will be the same in both calls of find.
The grep at the end removes information about identical input lines.
If it's GNU diff then you should just be able to point it at the two directories and use the -r option.
Otherwise, try using
for i in $(\ls -d ./dir1/*); do diff ${i} dir2; done
N.B. As pointed out by Dennis in the comments section, you don't actually need to do the command substitution on the ls. I've been doing this for so long that I'm pretty much doing this on autopilot and substituting the command I need to get my list of files for comparison.
Also I forgot to add that I do '\ls' to temporarily disable my alias of ls to GNU ls so that I lose the colour formatting info from the listing returned by GNU ls.
When working with git/svn or multiple git/svn instances on disk this has been one of the most useful things for me over the past 5-10 years, that somebody might find useful:
diff -burN /path/to/directory1 /path/to/directory2 | grep +++
or:
git diff /path/to/directory1 | grep +++
It gives you a snapshot of the different files that were touched without having to "less" or "more" the output. Then you just diff on the individual files.
In practice the question often arises together with some constraints. In that case following solution template may come in handy.
cd dir1
find . \( -name '*.txt' -o -iname '*.md' \) | xargs -i diff -u '{}' 'dir2/{}'
Here is a script to show differences between files in two folders. It works recursively. Change dir1 and dir2.
(search() { for i in $1/*; do [ -f "$i" ] && (diff "$1/${i##*/}" "$2/${i##*/}" || echo "files: $1/${i##*/} $2/${i##*/}"); [ -d "$i" ] && search "$1/${i##*/}" "$2/${i##*/}"; done }; search "dir1" "dir2" )
Try this:
diff -rq /path/to/folder1 /path/to/folder2
I need to rename files names like this
transform.php?dappName=Test&transformer=YAML&v_id=XXXXX
to just this
XXXXX.txt
How can I do it?
I understand that i need more than one mv command because they are at least 25000 files.
Easiest solution is to use "mmv"
You can write:
mmv "long_name*.txt" "short_#1.txt"
Where the "#1" is replaced by whatever is matched by the first wildcard.
Similarly #2 is replaced by the second, etc.
So you do something like
mmv "index*_type*.txt" "t#2_i#1.txt"
To rename index1_type9.txt to t9_i1.txt
mmv is not standard in many Linux distributions but is easily found on the net.
If you are using zsh you can also do this:
autoload zmv
zmv 'transform.php?dappName=Test&transformer=YAML&v_id=(*)' '$1.txt'
You write a fairly simple shell script in which the trickiest part is munging the name.
The outline of the script is easy (bash syntax here):
for i in 'transform.php?dappName=Test&transformer=YAML&v_id='*
do
mv $i <modified name>
done
Modifying the name has many options. I think the easiest is probably an awk one-liner like
`echo $i | awk -F'=' '{print $4}'`
so...
for i in 'transform.php?dappName=Test&transformer=YAML&v_id='*
do
mv $i `echo $i | awk -F'=' '{print $4}'`.txt
done
update
Okay, as pointed out below, this won't necessarily work for a large enough list of files; the * will overrun the command line length limit. So, then you use:
$ find . -name 'transform.php?dappName=Test&transformer=YAML&v_id=*' -prune -print |
while read
do
mv $reply `echo $reply | awk -F'=' '{print $4}'`.txt
done
Try the rename command
Or you could pipe the results of an ls into a perl regex.
You may use whatever you want to transform the name (perl, sed, awk, etc.). I'll use a python one-liner:
for file in 'transform.php?dappName=Test&transformer=YAML&v_id='*; do
mv $file `echo $file | python -c "print raw_input().split('=')[-1]"`.txt;
done
Here's the same script entirely in Python:
import glob, os
PATTERN="transform.php?dappName=Test&transformer=YAML&v_id=*"
for filename in glob.iglob(PATTERN):
newname = filename.split('=')[-1] + ".txt"
print filename, '==>', newname
os.rename(filename, newname)
Side note: you would have had an easier life saving the pages with the right name while grabbing them...
find -name '*v_id=*' | perl -lne'rename($_, qq($1.txt)) if /v_id=(\S+)/'
vimv lets you rename multiple files using Vim's text editing capabilities.
Entering vimv opens a Vim window which lists down all files and you can do pattern matching, visual select, etc to edit the names. After you exit Vim, the files will be renamed.
[Disclaimer: I'm the author of the tool]
I'd use ren-regexp, which is a Perl script that lets you mass-rename files very easily.
21:25:11 $ ls
transform.php?dappName=Test&transformer=YAML&v_id=12345
21:25:12 $ ren-regexp 's/transform.php.*v_id=(\d+)/$1.txt/' transform.php*
transform.php?dappName=Test&transformer=YAML&v_id=12345
1 12345.txt
21:26:33 $ ls
12345.txt
This should also work:
prfx='transform.php?dappName=Test&transformer=YAML&v_id='
ls $prfx* | sed s/$prfx// | xargs -Ipsx mv "$prfx"psx psx
this renamer command would do it:
$ renamer --regex --find 'transform.php?dappName=Test&transformer=YAML&v_id=(\w+)' --replace '$1.txt' *
Ok, you need to be able to run a windows binary for this.
But if you can run Total Commander, do this:
Select all files with *, and hit ctrl-M
In the Search field, paste "transform.php?dappName=Test&transformer=YAML&v_id="
(Leave Replace empty)
Press Start
It doesn't get much simpler than that.
You can also rename using regular expressions via this dialog, and you see a realtime preview of how your files are going to be renamed.