Category : C Source Code
Archive   : F2CSRC.ZIP
Filename : F2C.1

F2C(1) 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
current 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.

-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
`-w66', only Fortran 66 compatibility warnings are
suppressed.

The following options are peculiar to f2c.

-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.

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F2C(1) F2C(1)

-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.

-g Include original Fortran line numbers as comments.

-h 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.

-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-
precision operands.

-P Write a file.P of ANSI (or C++) prototypes for pro-
cedures defined in each input file.f or file.F. When
reading Fortran from standard input, write prototypes
at the beginning of standard output. Implies -A unless
option `-C++' is present. Option -Ps implies -P , and
gives exit status 4 if rerunning f2c may change proto-
types 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 values of REAL functions (including intrinsics) to
REAL.

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

-Tdir
Put temporary files in directory dir.

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

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F2C(1) F2C(1)

-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.

-!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.a
intrinsic function library

/usr/lib/libI77.a
Fortran 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

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F2C(1) F2C(1)

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.

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