
     F2C(1)		       UNIX System V			F2C(1)

     NAME
	  f2c -	Convert	Fortran	77 to C	or C++

     SYNOPSIS
	  f2c [	option ... ] file ...

     DESCRIPTION
	  F2c converts Fortran 77 source code in files with names end-
	  ing in `.f' or `.F' to C (or C++) source files in the	cur-
	  rent directory, with `.c' substituted	for the	final `.f' or
	  `.F'.	 If no Fortran files are named,	f2c reads Fortran from
	  standard input and writes C on standard output.  File	names
	  that end with	`.p' or	`.P' are taken to be prototype files,
	  as produced by option	`-P', and are read first.

	  The following	options	have the same meaning as in f77(1).

	  -C   Compile code to check that subscripts are within
	       declared	array bounds.

	  -I2  Render INTEGER and LOGICAL as short, INTEGER*4 as long
	       int.  Assume the	default	libF77 and libI77:  allow only
	       INTEGER*4 (and no LOGICAL) variables in INQUIREs.
	       Option `-I4' confirms the default rendering of INTEGER
	       as long int.

	  -I8  Assume 8-byte integer and logical, 4-byte REAL, 8-byte
	       double precison and complex, and 16-byte double complex
	       variables.  Appropriate changes to f2c.h may be needed.

	  -Idir
	       Look for	a non-absolute include file first in the
	       directory of the	current	input file, then in directo-
	       ries specified by -I options (one directory per
	       option).	 Options -I2, -I4  and -I8 have precedence, so,
	       e.g., a directory named 2 should	be specified by	-I./2 .

	  -onetrip
	       Compile DO loops	that are performed at least once if
	       reached.	 (Fortran 77 DO	loops are not performed	at all
	       if the upper limit is smaller than the lower limit.)

	  -U   Honor the case of variable and external names.  Fortran
	       keywords	must be	in lower case.

	  -u   Make the	default	type of	a variable `undefined' rather
	       than using the default Fortran rules.

	  -w   Suppress	all warning messages, or, if the option	is
	       `-w66', just Fortran 66 compatibility warnings.

	  The following	options	are peculiar to	f2c.

	  -A   Produce ANSI C (default,	starting 20020621).  For old-
	       style C,	use option -K.

     Page 1					     (printed 1/23/24)

     F2C(1)		       UNIX System V			F2C(1)

	  -a   Make local variables automatic rather than static
	       unless they appear in a DATA, EQUIVALENCE, NAMELIST, or
	       SAVE statement.

	  -C++ Output C++ code.

	  -c   Include original	Fortran	source as comments.

	  -cd  Do not recognize	cdabs, cdcos, cdexp, cdlog, cdsin, and
	       cdsqrt as synonyms for the double complex intrinsics
	       zabs, zcos, zexp, zlog, zsin, and zsqrt,	respectively,
	       nor dreal as a synonym for dble.

	  -cf  Do not report the current .f file except in error messages.

	  -ddir
	       Write `.c' files	in directory dir instead of the	cur-
	       rent directory.

	  -E   Declare uninitialized COMMON to be Extern (overridably
	       defined in f2c.h	as extern).

	  -ec  Place uninitialized COMMON blocks in separate files:
	       COMMON /ABC/ appears in file abc_com.c.	Option `-e1c'
	       bundles the separate files into the output file,	with
	       comments	that give an unbundling	sed(1) script.

	  -ext Complain	about f77(1) extensions.

	  -f   Assume free-format input: accept	text after column 72
	       and do not pad fixed-format lines shorter than 72 char-
	       acters with blanks.

	  -72  Treat text appearing after column 72 as an error.

	  -g   Include original	Fortran	line numbers in	#line lines.

	  -h   Emulate Fortran 66's treatment of Hollerith: try	to
	       align character strings on word (or, if the option is
	       `-hd', on double-word) boundaries.

	  -i2  Similar to -I2, but assume a modified libF77 and	libI77
	       (compiled with -Df2c_i2), so INTEGER and	LOGICAL	vari-
	       ables may be assigned by	INQUIRE	and array lengths are
	       stored in short ints.

	  -i90 Do not recognize	the Fortran 90 bit-manipulation
	       intrinsics btest, iand, ibclr, ibits, ibset, ieor, ior,
	       ishft, and ishftc.

	  -kr  Use temporary values to enforce Fortran expression
	       evaluation where	K&R (first edition) parenthesization
	       rules allow rearrangement.  If the option is `-krd',
	       use double precision temporaries	even for single-

     Page 2					     (printed 1/23/24)

     F2C(1)		       UNIX System V			F2C(1)

	       precision operands.

	  -P   Write a file.P of ANSI (or C++) prototypes for defini-
	       tions in	each input file.f or file.F.  When reading
	       Fortran from standard input, write prototypes at	the
	       beginning of standard output.  Option -Ps implies -P
	       and gives exit status 4 if rerunning f2c	may change
	       prototypes or declarations.

	  -p   Supply preprocessor definitions to make common-block
	       members look like local variables.

	  -R   Do not promote REAL functions and operations to DOUBLE
	       PRECISION.  Option `-!R'	confirms the default, which
	       imitates	f77.

	  -r   Cast REAL arguments of intrinsic	functions and values
	       of REAL functions (including intrinsics)	to REAL.

	  -r8  Promote REAL to DOUBLE PRECISION, COMPLEX to DOUBLE
	       COMPLEX.

	  -s   Preserve	multidimensional subscripts.  Suppressed by
	       option `-C' .

	  -Tdir
	       Put temporary files in directory	dir.

	  -trapuv
	       Dynamically initialize local variables, except those
	       appearing in SAVE or DATA statements, with values that
	       may help	find references	to uninitialized variables.
	       For example, with IEEE arithmetic, initialize local
	       floating-point variables	to signaling NaNs.

	  -w8  Suppress	warnings when COMMON or	EQUIVALENCE forces
	       odd-word	alignment of doubles.

	  -Wn  Assume n	characters/word	(default 4) when initializing
	       numeric variables with character	data.

	  -z   Do not implicitly recognize DOUBLE COMPLEX.

	  -!bs Do not recognize	backslash escapes (\", \', \0, \\, \b,
	       \f, \n, \r, \t, \v) in character	strings.

	  -!c  Inhibit C output, but produce -P	output.

	  -!I  Reject include statements.

	  -!i8 Disallow	INTEGER*8 , or,	if the option is `-!i8const',
	       permit INTEGER*8	but do not promote integer constants

     Page 3					     (printed 1/23/24)

     F2C(1)		       UNIX System V			F2C(1)

	       to INTEGER*8 when they involve more than	32 bits.

	  -!it Don't infer types of untyped EXTERNAL procedures	from
	       use as parameters to previously defined or prototyped
	       procedures.

	  -!P  Do not attempt to infer ANSI or C++ prototypes from
	       usage.

	  The resulting	C invokes the support routines of f77; object
	  code should be loaded	by f77 or with ld(1) or	cc(1) options
	  -lF77	-lI77 -lm.  Calling conventions	are those of f77: see
	  the reference	below.

     FILES
	  file.[fF]	   input file

	  *.c		   output file

	  /usr/include/f2c.h
			   header file

	  /usr/lib/libF77.aintrinsic function library

	  /usr/lib/libI77.aFortran I/O library

	  /lib/libc.a	   C library, see section 3

     SEE ALSO
	  S. I.	Feldman	and P. J. Weinberger, `A Portable Fortran 77
	  Compiler', UNIX Time Sharing System Programmer's Manual,
	  Tenth	Edition, Volume	2, AT&T	Bell Laboratories, 1990.

     DIAGNOSTICS
	  The diagnostics produced by f2c are intended to be self-
	  explanatory.

     BUGS
	  Floating-point constant expressions are simplified in	the
	  floating-point arithmetic of the machine running f2c,	so
	  they are typically accurate to at most 16 or 17 decimal
	  places.
	  Untypable EXTERNAL functions are declared int.
	  There	is no notation for INTEGER*8 constants.
	  Some intrinsic functions do not yet work with	INTEGER*8 .

     Page 4					     (printed 1/23/24)

