xref: /386bsd/usr/local/man/man1/f2c.1 (revision a2142627)
. \" Definitions of F, L and LR for the benefit of systems . \" whose -man lacks them... .. .. ..
F2C 1
.CT 1 prog_other
NAME
f\^2c - Convert Fortran 77 to C or C++
SYNOPSIS
f\^2c [ option ... ] file ...
DESCRIPTION
F2c converts Fortran 77 source code in files with names ending in .L .f or .L .F to C (or C++) source files in the current directory, with .L .c substituted for the final .L .f or .LR .F . If no Fortran files are named, f\^2c reads Fortran from standard input and writes C on standard output. File names that end with .L .p or .L .P are taken to be prototype files, as produced by option .LR -P , and are read first.

The following options have the same meaning as in f\^77 (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 .L -I4 confirms the default rendering of INTEGER as long int.

-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. If the option is .LR -w66 , only Fortran 66 compatibility warnings are suppressed.

The following options are peculiar to f\^2c .

-A Produce ANSI C. Default is old-style C.

-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.

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

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

-ext Complain about f\^77 (1) extensions.

-f Assume free-format input: accept text after column 72 and do not pad fixed-format lines shorter than 72 characters 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 .LR -hd , on double-word) boundaries.

-i2 Similar to -I2 , but assume a modified libF77 and libI77 (compiled with -Df\^2c_i2 ), so INTEGER and LOGICAL variables may be assigned by INQUIRE and array lengths are stored in short ints.

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

-P Write a file .P of ANSI (or C++) prototypes for definitions 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 f\^2c 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 .L -!R confirms the default, which imitates f\^77 .

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

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

-s Preserve multidimensional subscripts.

-T dir Put temporary files in directory dir.

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

-W n 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 (\e", \e', \e0, \e\e, \eb, \ef, \en, \er, \et, \ev) in character strings.

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

-!I Reject include statements.

-!i8 Disallow INTEGER*8.

-!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 f\^77 ; object code should be loaded by f\^77 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

.F /usr/include/f2c.h header file

.F /usr/lib/libF77.a intrinsic function library

.F /usr/lib/libI77.a Fortran I/O library

.F /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 f\^2c are intended to be self-explanatory.
BUGS
Floating-point constant expressions are simplified in the floating-point arithmetic of the machine running f\^2c , so they are typically accurate to at most 16 or 17 decimal places.

Untypable EXTERNAL functions are declared int .