Update info on the f77 I/O lib.		15 Feb., 1980

1) All instances of:
	if(!init) f_init();
   have been removed. f_init() is called from main.c on startup in the new
   libF77.a .

2) Backspace now allows non-seek files to reset the EOF flag.

3) The way SIGINT is handled in libF77/main.c has been changed.
   If the signal is not SIG_DFL, it is left alone as otherwise the
   program will be killed if run in the background and the user types DEL.

4) The ANSI fortran standard requires that I/O routines return to the caller
   on any error condition if iostat= is specified even if no err= or end=
   trap is specified. The implication of this is that the program must
   be prepared to deal with ALL I/O errors if iostat= is specified.
   If only one trap is specified, end= for example, the program must test the
   iostat variable for positive/non-zero after the I/O call since return
   will occur on any error. This seems awkward and I've chosen to make this
   feature optional. I am interested in other views on this.
   
   In the current version of the compiler (using the modified io.c),
   iostat= is used only to return status information from
   I/O calls but does not itself cause return on any I/O error. Only
   the traps, err= and end=, will cause a return/branch, and only for
   the specified trap(s).
   
   This feature has been made a compile time option in the current version
   of (modified) io.c It implements the standard correctly if compiled
   with -DKOSHER or -DIOSRETURN. Otherwise it executes as currently
   implemented.