operator
file (with open-modifier (& open-modifier)*)*
or
(binary-mode | text-mode)? (buffered | unbuffered)? file string-expression
The operator file retrieves the contents of a named file.
In certain limited cases, the file can be read in smaller chunks, allowing very large files to be processed
without requiring huge amounts of computer memory. These cases occur whenever the file expression is
used in the string expression of any of the following actions alone, or attached by ||
(join) to other string expressions:
put (the file expression must be the second argument),
output,
set (when performed on a stream),
set file, and
set referent.
file can also be used as the entire string expression argument of one of the following
actions:
submit,
do scan,
repeat scan,
do sgml-parse,
do xml-parse, and
using input as.