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If your compiler does not recognize ANSI C headers,
compile with KR_headers defined: either add -DKR_headers
to the definition of CFLAGS in the makefile, or insert
#define KR_headers
at the top of f2c.h , cabs.c , main.c , and sig_die.c .
Under MS-DOS, compile s_paus.c with -DMSDOS.
If you have a really ancient K&R C compiler that does not understand
void, add -Dvoid=int to the definition of CFLAGS in the makefile.
If you use a C++ compiler, first create a local f2c.h by appending
f2ch.add to the usual f2c.h, e.g., by issuing the command
make f2c.h
which assumes f2c.h is installed in /usr/include .
If your system lacks onexit() and you are not using an ANSI C
compiler, then you should compile main.c, s_paus.c, s_stop.c, and
sig_die.c with NO_ONEXIT defined. See the comments about onexit in
the makefile.
If your system has a double drem() function such that drem(a,b)
is the IEEE remainder function (with double a, b), then you may
wish to compile r_mod.c and d_mod.c with IEEE_drem defined.
On some systems, you may also need to compile with -Ddrem=remainder .
To check for transmission errors, issue the command
make check
This assumes you have the xsum program whose source, xsum.c,
is distributed as part of "all from f2c/src". If you do not
have xsum, you can obtain xsum.c by sending the following E-mail
message to netlib@netlib.bell-labs.com
send xsum.c from f2c/src
The makefile assumes you have installed f2c.h in a standard
place (and does not cause recompilation when f2c.h is changed);
f2c.h comes with "all from f2c" (the source for f2c) and is
available separately ("f2c.h from f2c").
Most of the routines in libF77 are support routines for Fortran
intrinsic functions or for operations that f2c chooses not
to do "in line". There are a few exceptions, summarized below --
functions and subroutines that appear to your program as ordinary
external Fortran routines.
If you use the REAL valued functions listed below (ERF, ERFC,
DTIME, and ETIME) with "f2c -R", then you need to compile the
corresponding source files with -DREAL=float. To do this, it is
perhaps simplest to add "-DREAL=float" to CFLAGS in the makefile.
1. CALL ABORT prints a message and causes a core dump.
2. ERF(r) and DERF(d) and the REAL and DOUBLE PRECISION
error functions (with x REAL and d DOUBLE PRECISION);
DERF must be declared DOUBLE PRECISION in your program.
Both ERF and DERF assume your C library provides the
underlying erf() function (which not all systems do).
3. ERFC(r) and DERFC(d) are the complementary error functions:
ERFC(r) = 1 - ERF(r) and DERFC(d) = 1.d0 - DERFC(d)
(except that their results may be more accurate than
explicitly evaluating the above formulae would give).
Again, ERFC and r are REAL, and DERFC and d are DOUBLE
PRECISION (and must be declared as such in your program),
and ERFC and DERFC rely on your system's erfc().
4. CALL GETARG(n,s), where n is an INTEGER and s is a CHARACTER
variable, sets s to the n-th command-line argument (or to
all blanks if there are fewer than n command-line arguments);
CALL GETARG(0,s) sets s to the name of the program (on systems
that support this feature). See IARGC below.
5. CALL GETENV(name, value), where name and value are of type
CHARACTER, sets value to the environment value, $name, of
name (or to blanks if $name has not been set).
6. NARGS = IARGC() sets NARGS to the number of command-line
arguments (an INTEGER value).
7. CALL SIGNAL(n,func), where n is an INTEGER and func is an
EXTERNAL procedure, arranges for func to be invoked when
signal n occurs (on systems where this makes sense).
8. CALL SYSTEM(cmd), where cmd is of type CHARACTER, passes
cmd to the system's command processor (on systems where
this can be done).
If your compiler complains about the signal calls in main.c, s_paus.c,
and signal_.c, you may need to adjust signal1.h suitably. See the
comments in signal1.h.
8. ETIME(ARR) and DTIME(ARR) are REAL functions that return
execution times. ARR is declared REAL ARR(2). The elapsed
user and system CPU times are stored in ARR(1) and ARR(2),
respectively. ETIME returns the total elapsed CPU time,
i.e., ARR(1) + ARR(2). DTIME returns total elapsed CPU
time since the previous call on DTIME.
9. CALL SYSTEM(cmd), where cmd is of type CHARACTER, passes
cmd to the system's command processor (on systems where
this can be done).
The makefile does not attempt to compile pow_qq.c, qbitbits.c,
and qbitshft.c, which are meant for use with INTEGER*8. To use
INTEGER*8, you must modify f2c.h to declare longint and ulongint
appropriately; then add pow_qq.o to the POW = line in the makefile,
and add " qbitbits.o qbitshft.o" to the makefile's F90BIT = line.
Following Fortran 90, s_cat.c and s_copy.c allow the target of a
(character string) assignment to be appear on its right-hand, at
the cost of some extra overhead for all run-time concatenations.
If you prefer the extra efficiency that comes with the Fortran 77
requirement that the left-hand side of a character assignment not
be involved in the right-hand side, compile s_cat.c and s_copy.c
with -DNO_OVERWRITE .
If your system lacks a ranlib command, you don't need it.
Either comment out the makefile's ranlib invocation, or install
a harmless "ranlib" command somewhere in your PATH, such as the
one-line shell script
exit 0
or (on some systems)
exec /usr/bin/ar lts $1 >/dev/null
If your compiler complains about the signal calls in main.c, s_paus.c,
and signal_.c, you may need to adjust signal1.h suitably. See the
comments in signal1.h.
By default, the routines that implement complex and double complex
division, c_div.c and z_div.c, call sig_die to print an error message
and exit if they see a divisor of 0, as this is sometimes helpful for
debugging. On systems with IEEE arithmetic, compiling c_div.c and
z_div.c with -DIEEE_COMPLEX_DIVIDE causes them instead to set both
the real and imaginary parts of the result to +INFINITY if the
numerator is nonzero, or to NaN if it vanishes.
The initializations for "f2c -trapuv" are done by _uninit_f2c(),
whose source is uninit.c, introduced June 2001. On IEEE-arithmetic
systems, _uninit_f2c should initialize floating-point variables to
signaling NaNs and, at its first invocation, should enable the
invalid operation exception. Alas, the rules for distinguishing
signaling from quiet NaNs were not specified in the IEEE P754 standard,
nor were the precise means of enabling and disabling IEEE-arithmetic
exceptions, and these details are thus system dependent. There are
#ifdef's in uninit.c that specify them for some popular systems. If
yours is not one of these systems, it may take some detective work to
discover the appropriate details for your system. Sometimes it helps
to look in the standard include directories for header files with
relevant-sounding names, such as ieeefp.h, nan.h, or trap.h, and
it may be simplest to run experiments to see what distinguishes a
signaling from a quiet NaN. (If x is initialized to a signaling
NaN and the invalid operation exception is masked off, as it should
be by default on IEEE-arithmetic systems, then computing, say,
y = x + 1 will yield a quiet NaN.)
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