1F2C(1) General Commands Manual F2C(1)
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6 f2c - Convert Fortran 77 to C or C++
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9 f2c [ option ... ] file ...
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12 F2c converts Fortran 77 source code in files with names ending in `.f'
13 or `.F' to C (or C++) source files in the current directory, with `.c'
14 substituted for the final `.f' or `.F'. If no Fortran files are named,
15 f2c reads Fortran from standard input and writes C on standard output.
16 File names that end with `.p' or `.P' are taken to be prototype files,
17 as produced by option `-P', and are read first.
18 The following options have the same meaning as in f77(1).
20 -C Compile code to check that subscripts are within declared array
22 bounds.
23 -I2 Render INTEGER and LOGICAL as short, INTEGER∗4 as long int.
25 Assume the default libF77 and libI77: allow only INTEGER∗4 (and
26 no LOGICAL) variables in INQUIREs. Option `-I4' confirms the
27 default rendering of INTEGER as long int.
28 -Idir Look for a non-absolute include file first in the directory of
30 the current input file, then in directories specified by -I
31 options (one directory per option). Options -I2 and -I4 have
32 precedence, so, e.g., a directory named 2 should be specified by
33 -I./2 .
34 -onetrip
36 Compile DO loops that are performed at least once if reached.
37 (Fortran 77 DO loops are not performed at all if the upper limit
38 is smaller than the lower limit.)
39 -U Honor the case of variable and external names. Fortran keywords
41 must be in lower case.
42 -u Make the default type of a variable `undefined' rather than
44 using the default Fortran rules.
45 -w Suppress all warning messages, or, if the option is `-w66', just
47 Fortran 66 compatibility warnings.
48 The following options are peculiar to f2c.
50 -A Produce ANSI C (default, starting 20020621). For old-style C,
52 use option -K.
53 -a Make local variables automatic rather than static unless they
55 appear in a DATA, EQUIVALENCE, NAMELIST, or SAVE statement.
56 -C++ Output C++ code.
58 -c Include original Fortran source as comments.
60 -cd Do not recognize cdabs, cdcos, cdexp, cdlog, cdsin, and cdsqrt
62 as synonyms for the double complex intrinsics zabs, zcos, zexp,
63 zlog, zsin, and zsqrt, respectively, nor dreal as a synonym for
64 dble.
65 -ddir Write `.c' files in directory dir instead of the current direc‐
67 tory.
68 -E Declare uninitialized COMMON to be Extern (overridably defined
70 in f2c.h as extern).
71 -ec Place uninitialized COMMON blocks in separate files: COMMON
73 /ABC/ appears in file abc_com.c. Option `-e1c' bundles the sep‐
74 arate files into the output file, with comments that give an
75 unbundling sed(1) script.
76 -ext Complain about f77(1) extensions.
78 -f Assume free-format input: accept text after column 72 and do not
80 pad fixed-format lines shorter than 72 characters with blanks.
81 -72 Treat text appearing after column 72 as an error.
83 -g Include original Fortran line numbers in #line lines.
85 -h Emulate Fortran 66's treatment of Hollerith: try to align char‐
87 acter strings on word (or, if the option is `-hd', on double-
88 word) boundaries.
89 -i2 Similar to -I2, but assume a modified libF77 and libI77 (com‐
91 piled with -Df2c_i2), so INTEGER and LOGICAL variables may be
92 assigned by INQUIRE and array lengths are stored in short ints.
93 -i90 Do not recognize the Fortran 90 bit-manipulation intrinsics
95 btest, iand, ibclr, ibits, ibset, ieor, ior, ishft, and ishftc.
96 -kr Use temporary values to enforce Fortran expression evaluation
98 where K&R (first edition) parenthesization rules allow re‐
99 arrangement. If the option is `-krd', use double precision tem‐
100 poraries even for single-precision operands.
101 -P Write a file.P of ANSI (or C++) prototypes for definitions in
103 each input file.f or file.F. When reading Fortran from standard
104 input, write prototypes at the beginning of standard output.
105 Option -Ps implies -P and gives exit status 4 if rerunning f2c
106 may change prototypes or declarations.
107 -p Supply preprocessor definitions to make common-block members
109 look like local variables.
110 -R Do not promote REAL functions and operations to DOUBLE PRECI‐
112 SION. Option `-!R' confirms the default, which imitates f77.
113 -r Cast REAL arguments of intrinsic functions and values of REAL
115 functions (including intrinsics) to REAL.
116 -r8 Promote REAL to DOUBLE PRECISION, COMPLEX to DOUBLE COMPLEX.
118 -s Preserve multidimensional subscripts. Suppressed by option `-C'
120 .
121 -Tdir Put temporary files in directory dir.
123 -trapuv
125 Dynamically initialize local variables, except those appearing
126 in SAVE or DATA statements, with values that may help find ref‐
127 erences to uninitialized variables. For example, with IEEE
128 arithmetic, initialize local floating-point variables to signal‐
129 ing NaNs.
130 -w8 Suppress warnings when COMMON or EQUIVALENCE forces odd-word
132 alignment of doubles.
133 -Wn Assume n characters/word (default 4) when initializing numeric
135 variables with character data.
136 -z Do not implicitly recognize DOUBLE COMPLEX.
138 -!bs Do not recognize backslash escapes (\", \', \0, \\, \b, \f, \n,
140 \r, \t, \v) in character strings.
141 -!c Inhibit C output, but produce -P output.
143 -!I Reject include statements.
145 -!i8 Disallow INTEGER*8 , or, if the option is `-!i8const', permit
147 INTEGER*8 but do not promote integer constants to INTEGER*8 when
148 they involve more than 32 bits.
149 -!it Don't infer types of untyped EXTERNAL procedures from use as
151 parameters to previously defined or prototyped procedures.
152 -!P Do not attempt to infer ANSI or C++ prototypes from usage.
154 The resulting C invokes the support routines of f77; object code should
156 be loaded by f77 or with ld(1) or cc(1) options -lF77 -lI77 -lm. Call‐
157 ing conventions are those of f77: see the reference below.
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160 file.[fF]
161 input file
162 *.c output file
164 /usr/include/f2c.h
166 header file
167 /usr/lib/libF77.a
169 intrinsic function library
170 /usr/lib/libI77.a
172 Fortran I/O library
173 /lib/libc.a
175 C library, see section 3
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178 S. I. Feldman and P. J. Weinberger, `A Portable Fortran 77 Compiler',
179 UNIX Time Sharing System Programmer's Manual, Tenth Edition, Volume 2,
180 AT&T Bell Laboratories, 1990.
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183 The diagnostics produced by f2c are intended to be self-explanatory.
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186 Floating-point constant expressions are simplified in the floating-
187 point arithmetic of the machine running f2c, so they are typically
188 accurate to at most 16 or 17 decimal places.
189 Untypable EXTERNAL functions are declared int.
190 There is no notation for INTEGER*8 constants.
191 Some intrinsic functions do not yet work with INTEGER*8 .
192 F2C(1)