Programming :: Basename With Command Substitutions And Xargs
Jun 17, 2011
I get this behavior on Slackware 13.37, which includes BASH 4.1.010. Yes, BASH is my shell. I have a file called a.flac and I'm in the directory that contains it.
The output of the ls command is expected:
Code:
ls *.flac
gives:
Code:
a.flac
Removing the extension with basename works as expected:
Code:
basename a.flac .flac
gives:
Code:
a
Putting the above command in a variable substitution works as expected:
Code:
echo `basename a.flac .flac`
gives:
Code:
a
Using xargs with ls and a variable substitution works as expected:
Code:
ls *.flac | xargs -i echo `echo {}`
gives:
Code:
a.flac
However, when I try to add the basename command to the above command, it stops working.
Code:
ls *.flac | xargs -i echo `basename {} .flac`
gives:
Code:
a.flac
Whereas the result I expect is:
Code:
a
Why is it not working, and how do I make it work?
I often want to extract some info using awk from a variable/filename while running other things using xargs and sh. Below is an example: Code: ls -1 *.txt | xargs -i sh -c 'NEW=`echo $0 | awk -F'_' '{print $1}'`; echo $NEW' {}
In the above case I would like to grab just the first field from a filename (delimited by '_') from within an sh command. This is a simplified example, where normally I would be doing some further data processing with the sh command(s).
The error message that I get is: Code: }`; echo $NEW: -c: line 0: unexpected EOF while looking for matching ``' }`; echo $NEW: -c: line 1: syntax error: unexpected end of file. I haven't been able to figure out how to escape the awk command properly.
I would like to ask the following: 1) ls -l |grep test -> this will grep every "ls -l" output line 2) ls -1 |xargs grep test -> this will grep every single file with test 3) ls -1 |xargs echo -> this will echo directory list 4) ls -1 |echo -> this does nothing!!!
My question is: how some command can receive input from "both sides" (grep can grep whole output or every single file - xargs, the same is for i.e. wc command). 4) echo does nothing (it's a single echo command).
I'm testing some multi-plat java code and I'm getting a bit frustrated with the Linux tests. I need to run the command: Code: $ java -jar /home/developer/TCO/TabletComicOptimizer.jar <file> <args[]> against all the files that match a specific criteria. I've tried various find syntax and I can't seem to get it right.
Normally I would just create a bash script and populate the results of find into an array and then just enumerate the collection but in this specific case I want to demonstrate this operation at the bash terminal.
I've tried things like: Code: ~/TCO $ find . -type f -iname "*.cb[rz]" | xargs java -jar TabletComicOptimizer.jar {} 1200x1800 ; Thinking that the {} is the substitution for each file returned by find but it's not working. How do I execute my java program against each result in the find operation?
I have an awk program that finds all files of a specific filename and deletes them from selected subdirectories. There is logic in the awk to avoid certain subdirectories, and this is initialized via a parameter in the beginning statement of the awk. The parameter should have all of the subdirectory names at the top level. This varies from time to time, so I cannot hard-code the value.I'm having a problem initializing the awk parameter using sed. I'm setting a variable (named subdir) using an "ls" command piped to "xargs". I'm then trying to substitute that value into the awk using the sed command.
Quote:Originally Posted by SimonJM It almost smacks of your script being wrapped up in something elseGot it sorted, did the logic in PHP and linked directly to ffmpeg
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I used the command shown below to remove a list of software using yum. It worked, but is there a way of doing this without using the -y option? I would like to review the results before the transaction takes place. I would like to use the same method for installing additional software after a clean install. cat filename | xargs yum -y remove
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I'm trying to find all zip files timestamped from the past 7 days, then unzip them into a different director.I tried the following, but it only unzipped one of three files that meet the 7 day criteria. What am I missing?Code:find /home/user/public_html/zip_files/ -iname "*.zip" -mtime -7 -print0 | xargs -n10 unzip -LL -o -d /home/user/public_html/another_directory/
$cmd If this script is executed, an error is generated. The reason written was that "The execution fails because the pipe is not expanded and is passed to date as an argument".What is meant by expansion of pipe. When we execute date | wc on the command line, it goes fine.then | is not treated as an argument. Why?
I am trying to learn how to pass more than a one-command startup for gnome-terminal.
I will give an example of what I'm trying to do here:
Code: #! /bin/bash # #TODO write this for gnome and xterm USAGE=" ${0##*/} [-x] [-g] code....
However, running with the -g option to invoke gnome-terminal, I get a "There was an error creating the child process for this terminal" error.
This same error occurs if the gnome-terminal line is changed to
Code: gnome-terminal -e mcTerm
Is there any way to pass more than one command on to gnome-terminal? I have tried various single and double quoting senarios and in a final attempt, I abstracted to an exported function all to no avail. Perhaps even though gnome-term is better at many things than xterm, xterm trumps it in this instance.
I am trying to grep multiple numbers from file, grep does have the -f option for that.
Code: grep -f <`seq 500 520` /etc/passwd I know this could be done with
Code: for i in `seq 500 520`; do grep "$i" /etc/passwd; done But my question is fare more behind this example. It is possible to redirect one command output which will be treat as a content of file for another command ?
Is there a command which can be used to run some other command on a few lines from a file or an o/p of some file. (the kind of role that -exec option does for the find command). (I have solved the purpose using a bash loop but would like to know if there exists a command).
What's the deal with this bloody commandI trying to do an update of a product.The -f is suppose to "force" the overwrite of existing files isn't it?Well every time I run the command it keeps asking me to allow it to overwrite the files.. the programs is too long for me to sit here hitting the "y" and "enter key"
I have a script that will build a list of hosts and it works fine Code: for ((i=$START; i<=$END; i++)); do echo "$NAME$i"; done But I need it to build the START and END on different number formats (i.e. 1 -> 10, 01->10, 001 ->010)
I am trying to use the seq command but can't get it to work quite right with the -w flag in the following Code: for ((myseq=$START; myseq<=$END; myseq ++)) do echo "$NAME${myseq}" done I am fully aware that this syntax is probably wrong, and need to know how to correct it.
Is anyone familiar with the Minix OS? i want to know what is the Process to add a new command in Minix that uses system call served by the memory manager server
