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Full Discussion: Usage of '-' in eval command.
Top Forums Shell Programming and Scripting Usage of '-' in eval command. Post 302878493 by rbatte1 on Friday 6th of December 2013 10:40:03 AM
Old 12-06-2013
The hyphen can be used in CoBOL code, but it is considered as plain text for Unix shells. I've fallen across this the other way around when I wanted to set a variable to a value built from another variable like this:-
Code:
fileheader=myfile
rundate=`date +%Y%m%d`
filename=$fileheader_$rundate

I wanted to end up with myfile_20131206 as the filename format and I got very confused because it always evaluated to just 20131206 (or whatever the date was)

This was because the underscore is considered part of the variable name and the variable fileheader_ was undefined. This is not pretty, but I had to change the code to read:-
Code:
fileheader=myfile
rundate=`date +%Y%m%d`
filename=${fileheader}_$rundate

.... and learn from my error.

I too would like to know what you are actually trying to achieve. We might have a better way to do it, save you some hassle and provide something for others to read and learn from. Indeed, I'm quite happy to learn myself if there is a better way than I am currently using.



Robin
This User Gave Thanks to rbatte1 For This Post:
Kuldip
 

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LEARN ABOUT OPENDARWIN

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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