NAME

       f2c - Convert Fortran 77 to C or C++

SYNOPSIS

       f2c [ option ...  ] file ...

DESCRIPTION

       F2c converts Fortran 77 source code in files with names ending 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.

       -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
              directories 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 per‐
              formed 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  warn‐
              ings.

       The following options are peculiar to f2c.

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

       -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 current 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 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 `-hd', on double-word) boundaries.

       -i2    Similar  to  -I2, but assume a modified libF77 and libI77 (compiled with -Df2c_i2), so INTEGER and
              LOGICAL variables 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) parenthe‐
              sization 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 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 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 arith‐
              metic, 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-!I   Reject include statements.

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

       -v, --version
              Print the version number of f2c

       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/libf2c.a
              static link intrinsic and I/O library

       /usr/lib/libf2c_i2.a
              static link intrinsic and I/O library for use with files translated using the -i2 f2c option

       /usr/lib/libf2c.so
              shared object intrinsic and I/O library

       /usr/lib/libf2c_i2.so
              shared object intrinsic and I/O library for use with files translated using the -i2 f2c option

       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  run‐
       ning 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 .

                                                                                                          F2C(1)