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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 OSX

set_color

set_color(1)							       fish							      set_color(1)

NAME

       set_color - set_color - set the terminal color

set_color - set the terminal color
   Synopsis
       set_color [-v --version] [-h --help] [-b --background COLOR] [COLOR]

   Description
       Change the foreground and/or background color of the terminal. COLOR is one of black, red, green, brown, yellow, blue, magenta, purple,
       cyan, white and normal.

       o -b, --background Set the background color

       o -c, --print-colors Prints a list of all valid color names

       o -h, --help Display help message and exit

       o -o, --bold Set bold or extra bright mode

       o -u, --underline Set underlined mode

       o -v, --version Display version and exit

       Calling set_color normal will set the terminal color to whatever is the default color of the terminal.

       Some terminals use the --bold escape sequence to switch to a brighter color set. On such terminals, set_color white will result in a grey
       font color, while set_color --bold white will result in a white font color.

       Not all terminal emulators support all these features. This is not a bug in set_color but a missing feature in the terminal emulator.

       set_color uses the terminfo database to look up how to change terminal colors on whatever terminal is in use. Some systems have old and
       incomplete terminfo databases, and may lack color information for terminals that support it. Download and install the latest version of
       ncurses and recompile fish against it in order to fix this issue.

Version 1.23.1							  Sun Jan 8 2012						      set_color(1)
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