bash: variables inside 'while'

[Gabriel Zachmann]

Consider this:

    xx=1
    cat file |
    while read p l
    do
        xx=$p
        echo xx=$xx
        break
    done
    echo xx=$xx

As output I get:

    xx=grid
    xx=1

(the first line of my 'file' contains the word grid).

ARGH! why is the variable 'xx' reset outside the 'while' loop???

With a simpler example:

    xx=1; while true; do xx=2; echo xx=$xx; break; done; echo xx=$xx

everything is fine, and I get the output:

    xx=2
    xx=2

This happens with version 2.05.8(1) (under redhat 7.1).

what's even more surprising is that the first example (with the 'cat')
works fine on the bash under cygwin (I don't recall right now which version).


HTH,
Gab.

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