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Full Discussion: In need of explanation
Top Forums UNIX for Dummies Questions & Answers In need of explanation Post 302373263 by skmdu on Friday 20th of November 2009 12:27:45 AM
Old 11-20-2009
Hi,

Code:
Meaning of different operator.. This might help you to understand about %% and ##

Operator "#" means "delete from the left, to the first case of what follows."
         $ x="This is my test string."
 $ echo ${x#* }

is my test string.


Operator "##" means "delete from the left, to the last case of what follows."                   
$ x="This is my test string."
$ echo ${x##* }

string.

Operator "%" means "delete from the right, to the first case of what follows."
                     
$ x="This is my test string."
$ echo ${x% *}

This is my test


Operator "%%" means "delete from the right, to the last case of what follows."
                     
$ x="This is my test string."
$ echo ${x%% *}

This

Now come to your example.

Code:
file1='Jane Mid Doe.txt'
newfile='Jane.txt'
 
 
1) ext=${file1##*.}  
    ## delete from left to last match. so here pattern is '*.' so left to right last match will give txt. ( it deletes Jane Mid Doe. ). Now ext = txt

2) filename=${file%%.???} ( I think here its not file, its file1).
  %% right to left to last match. and ? matches single character
so filename will Jane Mid Doe

3) set -- $filename
This is to set the $filename as an environment. so you can access through  $1, $2.. variables.
now $1 - Jane , $2 - Mid  and $3 - Doe
4) newfile="1.$extension" 
so in this statement you have to change 1 to $1

 

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LEARN ABOUT DEBIAN

xclip-copyfile

XCLIP-COPYFILE(1)					      General Commands Manual						 XCLIP-COPYFILE(1)

NAME

       xclip-copyfile, xclip-cutfile, xclip-pastefile - copy and move files via the X clipboard

SYNOPSIS

       xclip-copyfile [-p] FILES...

       xclip-cutfile [-p] FILES...

       xclip-pastefile

DESCRIPTION

       xclip-copyfile copies files into the X clipboard, recursing into directories.

       xclip-cutfile copies the files, but also deletes them afterwards.

       -p     preserve path formation

       xclip-pastefile pastes the files out of the clipboard

EXAMPLES

       Copying a file to a remote host

       [maggie.lkpg.cendio.se ~]$ echo "A file created on ${HOSTNAME}" > file1
       [maggie.lkpg.cendio.se ~]$ xclip-copyfile file1
       [sofie.homeip.net ~/doc]$ xclip-pastefile
       file1
       [sofie.homeip.net ~/doc]$ cat file1
       A file created on maggie.lkpg.cendio.se

       Copying an entire tree structure

       [sofie.homeip.net ~]$ xclip-copyfile doc
       [maggie.lkpg.cendio.se ~/tmp]$ xclip-pastefile
       doc/
       doc/letter-mom-april.txt
       doc/file1
       doc/letter-dad-march.txt

       Copying files with preserved path information

       [maggie.lkpg.cendio.se ~]$ xclip-copyfile -p /etc/sysconfig/grub
       tar: Removing leading `/' from member names
       [sofie.homeip.net ~/tmp]$ xclip-pastefile
       etc/sysconfig/grub
       [sofie.homeip.net ~/tmp]$ ls etc/sysconfig/grub
       etc/sysconfig/grub

       Moving files

       [sofie.homeip.net ~]$ ls letter-brother-may.txt
       letter-brother-may.txt
       [sofie.homeip.net ~]$ xclip-cutfile letter-brother-may.txt
       [sofie.homeip.net ~]$ ls letter-brother-may.txt
       ls: cannot access letter-brother-may.txt: No such file or directory
       [sofie.homeip.net ~]$ cd doc
       [sofie.homeip.net ~/doc]$ xclip-pastefile
       letter-brother-may.txt

AUTHORS

       This  manual  page  was written by Maximilian Gass <mxey@cloudconnected.org> for the Debian project. It may be used for everything else, of
       course.

																 XCLIP-COPYFILE(1)
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