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Full Discussion: Commenting out "expr" creates weird behavior
Top Forums Shell Programming and Scripting Commenting out "expr" creates weird behavior Post 302873085 by royalibrahim on Monday 11th of November 2013 06:34:12 AM
Old 11-11-2013
Commenting out "expr" creates weird behavior
This really puzzles me. The following code gives me the error 'expr: syntax error' when I try to do multi-line comment using here document
Code:
<<EOF
echo "Sum is: `expr $1 + $2`"
EOF

Even if I explicitly comment out the line containing the expr using "#", the error message would still exist
Code:
<<EOF
#echo "Sum is: `expr $1 + $2`"
EOF

And I observed that this happens only when I supply the 2nd operand to the expr as variable. If I hardcode it to a numeric value then the error message would disappear, that is
Code:
<<EOF
echo "Sum is: `expr $1 + 2`"   # expr's second argument numeric value is hard coded, no error now
EOF

Could anyone enlighten me on this?
 

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LEARN ABOUT NETBSD

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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