PerlIO::scalar - support module for in-memory IO.
open($fh,"<",\$scalar); open($fh,">",\$scalar);
or
open($fh,"<:scalar",\$scalar); open($fh,">:scalar",\$scalar);
PerlIO::scalar only exists to use XSLoader to load C code that provides
support for treating a scalar as an "in memory" file.
All normal file operations can be performed on the handle. The scalar
is considered a stream of bytes. Currently fileno($fh) returns undef.