DATA is a plain, ordinary file handle to the source file, but it's open for reading (not writing). I don't know how to convert a handle opened for reading into a handle opened for writing (if it's even possible), but you can open a new handle to the current file, and use tell(DATA) to find the location of the start of the data. 

die("Not safe for setuid") if ${^TAINT};

open(my $fh, ">>", __FILE__)
   or die("open: $!\n");

( my $data_pos = tell(DATA) ) >= 0
   or die("tell: $!\n");

truncate($fh, $data_pos)
   or die("truncate: $!\n");

say($fh "bar")
   or die("say: $!\n");

__DATA__
foo

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In reply to Re: Is it possible to modify __DATA__ via the DATA file handle or otherwise? by ikegami
in thread Is it possible to modify __DATA__ via the DATA file handle or otherwise? by YenForYang

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