I've seen that close ARGV can close the currently processed file, but it would seem that ARGV isn't actually a file handle, so I can't use it in a read call. Is there any way to get the current file handle, or am I going to have to explicitly open the files myself?
... but it would seem that ARGV isn't actually a file handle, so I can't use it in a read call
ARGV is a filehandle and it can be used within read.
To cite from perlvar:
... a plain filehandle corresponding to the last file opened by
<>"*
So it is a filehandle and it can be used within read. But you need to have to use <> first so that the file gets actually opened. And it will not magically continue with the next file as <> would do.
To test simply do (UNIX shell syntax, you might need to adapt this for Windows):
perl -e '<>; read(ARGV, my $buf, 10); print $buf' file
The <> will open the given file and read the first line. The read then will read the next 10 bytes from the same file.