describe more missing features

[craig@jcb-sc.com]

Committed, to both mainline and release branch.

        tq vm, (burley)


Sat Jun  5 23:50:36 1999  Craig Burley  <craig@jcb-sc.com>

	* g77.texi: Describe a few more missing features people
	have emailed me about.

*** g77-e/gcc/f/g77.texi.~1~	Fri Jun  4 10:11:05 1999
--- g77-e/gcc/f/g77.texi	Sat Jun  5 23:44:26 1999
***************
*** 3,7 ****
  @setfilename g77.info
  
! @set last-update 1999-06-04
  @set copyrights-g77 1995-1999
  
--- 3,7 ----
  @setfilename g77.info
  
! @set last-update 1999-06-06
  @set copyrights-g77 1995-1999
  
*************** GNU Fortran dialects:
*** 11419,11422 ****
--- 11419,11423 ----
  * Fortran Preprocessor::
  * Bit Operations on Floating-point Data::
+ * Really Ugly Character Assignments::
  
  New facilities:
*************** New facilities:
*** 11427,11430 ****
--- 11428,11432 ----
  * Support for Threads::
  * Increasing Precision/Range::
+ * Enabling Debug Lines::
  
  Better diagnostics:
*************** Run-time facilities:
*** 11446,11449 ****
--- 11448,11453 ----
  * Uninitialized Variables at Run Time::
  * Portable Unformatted Files::
+ * Better List-directed I/O::
+ * Default to Console I/O::
  
  Debugging:
*************** END
*** 12096,12099 ****
--- 12100,12121 ----
  @end smallexample
  
+ @node Really Ugly Character Assignments
+ @subsection Really Ugly Character Assignments
+ 
+ An option such as @samp{-fugly-char} should be provided
+ to allow
+ 
+ @smallexample
+ REAL*8 A1
+ DATA A1 / '12345678' /
+ @end smallexample
+ 
+ and:
+ 
+ @smallexample
+ REAL*8 A1
+ A1 = 'ABCDEFGH'
+ @end smallexample
+ 
  @node POSIX Standard
  @subsection @code{POSIX} Standard
*************** processors).
*** 12176,12179 ****
--- 12198,12212 ----
  A package such as PVM might help here.
  
+ @node Enabling Debug Lines
+ @subsection Enabling Debug Lines
+ @cindex debug line
+ @cindex comment line, debug
+ 
+ An option such as @samp{-fdebug-lines} should be provided
+ to turn fixed-form lines beginning with @samp{D}
+ to be treated as if they began with a space,
+ instead of as if they began with a @samp{C}
+ (as comment lines).
+ 
  @node Better Warnings
  @subsection Better Warnings
*************** only incur overhead when they are read o
*** 12470,12473 ****
--- 12503,12549 ----
  format.)  A future @code{g77} runtime library should use such
  techniques.
+ 
+ @node Better List-directed I/O
+ @subsection Better List-directed I/O
+ 
+ Values output using list-directed I/O
+ (@samp{PRINT *, R, D})
+ should be written with a field width, precision, and so on
+ appropriate for the type (precision) of each value.
+ 
+ (Currently, no distinction is made between single-precision
+ and double-precision values
+ by @code{libf2c}.)
+ 
+ It is likely this item will require the @code{libg77} project
+ to be undertaken.
+ 
+ In the meantime, use of formatted I/O is recommended.
+ While it might be of little consolation,
+ @code{g77} does support @samp{FORMAT(F<WIDTH>.4)}, for example,
+ as long as @samp{WIDTH} is defined as a named constant
+ (via @code{PARAMETER}).
+ That at least allows some compile-time specification
+ of the precision of a data type,
+ perhaps controlled by preprocessing directives.
+ 
+ @node Default to Console I/O
+ @subsection Default to Console I/O
+ 
+ The default I/O units,
+ specified by @samp{READ @var{fmt}},
+ @samp{READ (UNIT=*)},
+ @samp{WRITE (UNIT=*)}, and
+ @samp{PRINT @var{fmt}},
+ should not be units 5 (input) and 6 (output),
+ but, rather, unit numbers not normally available
+ for use in statements such as @code{OPEN} and @code{CLOSE}.
+ 
+ Changing this would allow a program to connect units 5 and 6
+ to files via @code{OPEN},
+ but still use @samp{READ (UNIT=*)} and @samp{PRINT}
+ to do I/O to the ``console''.
+ 
+ This change probably requires the @code{libg77} project.
  
  @node Labels Visible to Debugger