xargs interview questions
Top xargs frequently asked interview questions
Why does this not work?
ls *.txt | xargs cat > all.txt
(I want to join the contents of all text files into a single 'all.txt' file.)
find with -exec should also work, but I would really like to understand the xargs syntax.
Thanks
Source: (StackOverflow)
I want to know what is the difference between this
ls | xargs rm
ls | xargs -i{} rm {}
Both are working for me
Source: (StackOverflow)
In Linux, you can use xargs -d,
to quickly run the hostname
command against four different servers with sequential names as follows:
echo -n 1,2,3,4 |xargs -d, -I{} ssh root@www{}.example.com hostname
It looks like the OSX xargs command does not support the delimiter parameter. Can you achieve the same result with a differently formatted echo
, or through some other command-line utility?
Source: (StackOverflow)
What would be the easiest way to go about rsyncing the n newest files in a directory to a remote server?
Source: (StackOverflow)
I'm trying to execute a sequence of commands on a list of files one by one. I was wondering if it is possible to use xargs something on the lines of
ls *.txt | xargs -n 1 -I {} cat {} | grep foo > {}.foo
Where
cat {} | grep foo > {}.foo
is the command I want to execute on each file.
Source: (StackOverflow)
I'm using Mac 10.7.5 and on a bash shell. I'm trying to find instances of a string in a group of files but keep getting this error
Daves-MacBook-Pro:folder davea$ find . -name "*" | xargs grep 'state-icons'
xargs: grep: Argument list too long
How can I run the command (or a similar one) to avoid this error?
Source: (StackOverflow)
I have this command:
find $1 | xargs touch
But files with '
characters in their names fail with "xargs: unmatched single quote", and I guess other special characters would cause the same problem.
How can I escape the output so this command works with all filenames?
Source: (StackOverflow)
The target is not to list temp/run*.*
files. The target is to understand why the second command does not work.
First command:
find . \( -name 'temp' \) -print0 | xargs -0 -L 1 -I datafind ls -ltr datafind
list all the files inside temp folders from actual directory
Second command:
find . \( -name 'temp' \) -print0 | xargs -0 -L 1 -I datafind ls -ltr datafind/run*.*
gives cannot access error on every directory that worked with the previous command.
I searched and read man pages and examples but I can not find why the second command does not work. Any clue, please?
Source: (StackOverflow)
I am seeking for a command that would re-create a whole tree of files in a different directory. I would prefer to have all symlinks absolute. Can I do that with a find and xargs? ;-)
Source: (StackOverflow)
I need to convert videos but I don't know where are they, so I need to find
them. How can I give the result and an output file name to ffmpeg with xargs ?
I already find out that I can construct the two parameter with the command
find . -iname "*.mov" -printf "%p %f\n"
I can't find anything related in the xargs
manual.
I want something like this:
find . -iname "*.mov" -printf "%p %f\n" | xargs ffmpeg -i {param1} -f flv {param2}
How can I do this ?
Source: (StackOverflow)
I have a directory that has 10144911 files in it. So far I've tried the following:
for f in ls; do sed -i -e 's/blah/blee/g' $f; done
Crashed my shell, the ls
is in a tilda but i can't figure out how to make one.
ls | xargs -0 sed -i -e 's/blah/blee/g'
Too many args for sed
find . -name "*.txt" -exec sed -i -e 's/blah/blee/g' {} \;
Couldn't fork any more no more memory
Any other ideas on how to create this kind command? The files don't need to communicate with each other. ls | wc -l
seems to work (very slow) so it must be possible.
Source: (StackOverflow)
Feeling like an idiot right now. Why does this not work?
echo "/some/directory/path" | xargs -n1 cd
Source: (StackOverflow)
I was trying to find all files of a certain type spread out in subdirectories, and for my purposes I only needed the filename. I tried stripping out the path component via basename
, but it did't work with xargs
:
$ find . -name '*.deb' -print | xargs basename
basename: extra operand `./pool/main/a/aalib/libaa1_1.4p5-37+b1_i386.deb'
Try `basename --help' for more information.
I get the same thing (exactly the same error) with either of these variations:
$ find . -name '*.deb' -print0 | xargs -0 basename
$ find . -name '*.deb' -print | xargs basename {}
This, on the other hand, works as expected:
$ find . -name '*.deb' -exec basename {} \;
foo
bar
baz
This happens on up-to-date Cygwin and Debian 5.0.3. My diagnosis is that xargs is for some reason passing two input lines to basename, but why? What's going on here?
Source: (StackOverflow)
e.g. directory containing jpeg files: how to easily open just the most recent jpeg in the current directory?
Source: (StackOverflow)