06-21-2010
Thanks. I get that since all the special symbols like |,",',; all are evaluated before substitution takes place. Hence, in the case of $cmd, since no specia symbols were initially found, cmd was substituted for "date | wc" and | was taken as an argument to date (as | now has no meaning).
One question though, why do call evaluating the special symbols like | as expanding it? Does it mean that a special code for these symbols is inserted there when they're expanded ?
Also, it seems that there is another function of eval. When there are no substitutions to be made, then eval just removes the special symbols like '' and backslash. Like in the following :
eval echo \\l
eval echo \\\k
eval echo 'h'
I'm using bash shell
Last edited by daudiam; 06-21-2010 at 12:46 AM..
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