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Weird behavior of backslash, please help!!

 
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# 1  
Old 04-06-2011
Weird behavior of backslash, please help!!
Hi I am getting absurd behavior of escape character in echos as followed:
Code:
oinlcso003{arsadm} #: echo "\as shdd"
\as shdd
oinlcso003{arsadm} #: echo "Well, isn't that \"special\"?"
Well, isn't that "special"?
oinlcso003{arsadm} #: echo "Well, isn't that \special\?"
Well, isn't that \special\?
oinlcso003{arsadm} #: echo "Well, isn't that \$special\$?"
Well, isn't that $special$?
oinlcso003{arsadm} #: echo "Well, isn't that \$ special \$?"
Well, isn't that $ special $?
oinlcso003{arsadm} #: echo "Well, isn't that \#special\#?"
Well, isn't that \#special\#?
oinlcso003{arsadm} #: echo "Well, isn't that \'special\'?"
Well, isn't that \'special\'?
oinlcso003{arsadm} #: echo "Well, isn't that \' special \'?"
Well, isn't that \' special \'?
oinlcso003{arsadm} #: echo "Well, isn't that \\' special \'?"
Well, isn't that \' special \'?
oinlcso003{arsadm} #: 
oinlcso003{arsadm} #: echo "Well, isn't that \\\' special \'?"
Well, isn't that \\' special \'?
oinlcso003{arsadm} #: echo "Well, isn't that \\\'\\ special \'?"
Well, isn't that \\'\ special \'?

# 2  
Old 04-06-2011
Hi.

There's nothing absurd about it, really.

a, and s have no special meaning. Single quotes have no special meaning inside double quotes, # doesn't have special meaning inside any quotes, escaping a slash gives a literal slash, escaping a double quote inside double quotes gives a literal double quote, and a slash followed by any character which has no special meaning gives a literal slash.
This User Gave Thanks to Scott For This Post:
nixhead
# 3  
Old 04-06-2011
Thanks @scottn, but I hope more answers will more clarify the concept Smilie
# 4  
Old 04-07-2011
a little bit of google led me to this
Quoting characters

Using double quotes the literal value of all characters enclosed is preserved, except for the dollar sign, the backticks (backward single quotes, ``) and the backslash.
The dollar sign and the backticks retain their special meaning within the double quotes.
The backslash retains its meaning only when followed by dollar, backtick, double quote, backslash or newline. Within double quotes, the backslashes are removed from the input stream when followed by one of these characters. Backslashes preceding characters that don't have a special meaning are left unmodified for processing by the shell interpreter.
A double quote may be quoted within double quotes by preceding it with a backslash.
Code:
franky ~> echo "$date"
20021226

franky ~> echo "`date`"
Sun Apr 20 11:22:06 CEST 2003

franky ~> echo "I'd say: \"Go for it!\""
I'd say: "Go for it!"

franky ~> echo "\"
More input>"

franky ~> echo "\\"
\

 
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