Re^2: Bourne Shell: Variable defined?

[Maarten Litmaath]

gwyn at smoke.BRL.MIL (Doug Gwyn ) writes:
\In article <1819 at umbc3.UMBC.EDU> rostamia at umbc3.UMBC.EDU (Rouben Rostamian) writes:
\>In C Shell the variable $?foo returns true or false (0 of 1, really)
\>depending on whether or not the variable "foo" has been already defined.

\	if [ X"$foo" = X ]
\	then	:	# doesn't exist or is an empty string

The question was: "Has it been defined?"
Ergo, if $foo is an empty string, it IS defined and your test fails.
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