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C:\Dokumente und Einstellungen\Administrator>perldoc -f pos
pos SCALAR
pos Returns the offset of where the last "m//g" search left off for
the variable in question ($_ is used when the variable is not
specified). Note that 0 is a valid match offset. "undef"
indicates that the search position is reset (usually due to
match failure, but can also be because no match has yet been
performed on the scalar). "pos" directly accesses the location
used by the regexp engine to store the offset, so assigning to
"pos" will change that offset, and so will also influence the
"\G" zero-width assertion in regular expressions. Because a
failed "m//gc" match doesn't reset the offset, the return from
"pos" won't change either in this case. See perlre and perlop.