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Full Discussion: A sed doubt - need explanation
Top Forums Shell Programming and Scripting A sed doubt - need explanation Post 302240088 by royalibrahim on Thursday 25th of September 2008 03:05:33 AM
Old 09-25-2008
But in this code:
Code:
echo dogdog | sed -r s/\(.*\)\\1/cat/

I have 3 doubts:
1) I am getting the output as 'cat' but, if I wrapped the sed command inside single quotes, the output is 'dogdog', why this change?
2) why the syntax is '\\1' and not as '\1' in sed? it reports error if I change so
3) why it is not '/\1'?

N.B: echo dogdog | sed -r 's/(.*)\1/cat/' # Ans: cat
Last edited by royalibrahim; 09-25-2008 at 04:11 AM..
 

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LEARN ABOUT DEBIAN

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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