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.

       -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 and -I4 have prece‐
              dence, 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.

       -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)