filter i/o in C - (nf)

[utzoo!decvax!harpo!ihnp4!ixn5c!inuxc!pur-ee!uiucdcs!bcase]

#R:decvax:-40500:uiucdcs:27600006:000:155
uiucdcs!bcase    Jan 27 22:08:00 1983

What?  The C language says NOTHING about I/O!  You are referring to an
operating system consideration.  And to address that point, UN*X lets
you do it....