Hello harangzsolt33,

Angle brackets around a filehandle are a special Perl construct for calling the built-in readline function, which (like most Perl functions) behaves differently according to the context in which it appears. From the documentation:

In scalar context, each call reads and returns the next line until end-of-file is reached, whereupon the subsequent call returns undef. In list context, reads until end-of-file is reached and returns a list of lines.

The line my $L = <STDIN>; supplies a scalar context, and so only one line is read since readline is called only once.

By contrast, the line print <STDIN>; supplies a list context (see print), so multiple lines may be read in by a single call.

Change your second example as follows: my @L = <STDIN>; print @L; and you will see the same behaviour as in the first example. On Windows (where ^Z signals end-of-file):

12:31 >perl -wE "my @L = <STDIN>; print @L;"
abc
def
ghi
^Z
abc
def
ghi

12:31 >

[download]

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: Printing from stdin to stdout by Athanasius
in thread Printing from stdin to stdout by harangzsolt33

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