As shipped, "makefile" is a copy of "makefile.u", a Unix makefile. Variants for other systems have names of the form makefile.* and have initial comments saying how to invoke them. You may wish to copy one of the other makefile.* files to makefile. If you use a C++ compiler, first say make hadd to create a suitable f2c.h from f2c.h0 and f2ch.add. Otherwise, make f2c.h will just copy f2c.h0 to f2c.h . 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 . If your system lacks onexit() and you are not using an ANSI C compiler, then you should compile main.c with NO_ONEXIT defined. See the comments about onexit in makefile.u. 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. To check for transmission errors, issue the command make check or make -f makefile.u check This assumes you have the xsum program whose source, xsum.c, is distributed as part of "all from f2c/src", and that it is installed somewhere in your search path. If you do not have xsum, you can obtain xsum.c by sending the following E-mail message to netlib@netlib.org send xsum.c from f2c/src For convenience, the f2c.h0 in this directory is a copy of netlib's "f2c.h from f2c". It is best to install f2c.h in a standard place, so "include f2c.h" will work in any directory without further ado. Beware that the makefiles do not cause recompilation when f2c.h is changed. On machines, such as those using a DEC Alpha processor, on which sizeof(short) == 2, sizeof(int) == sizeof(float) == 4, and sizeof(long) == sizeof(double) == 8, it suffices to modify f2c.h by removing the first occurrence of "long " on each line containing "long ". On Unix systems, you can do this by issuing the commands mv f2c.h f2c.h0 sed 's/long int /int /' f2c.h0 >f2c.h On such machines, one can enable INTEGER*8 by uncommenting the typedefs of longint and ulongint in f2c.h and adjusting them, so they read typedef long longint; typedef unsigned long ulongint; and by compiling libf2c with -DAllow_TYQUAD, as discussed below. Most of the routines in libf2c 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 n occurs (on systems where this makes sense). 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). 10. CALL FLUSH flushes all buffers. 11. FTELL(i) is an INTEGER function that returns the current offset of Fortran unit i (or -1 if unit i is not open). 12. CALL FSEEK(i, offset, whence, *errlab) attemps to move Fortran unit i to the specified offset: absolute offset if whence = 0; relative to the current offset if whence = 1; relative to the end of the file if whence = 2. It branches to label errlab if unit i is not open or if the call otherwise fails. The routines whose objects are makefile.u's $(I77) are for I/O. The following comments apply to them. If your system lacks /usr/include/local.h , then you should create an appropriate local.h in this directory. An appropriate local.h may simply be empty, or it may #define VAX or #define CRAY (or whatever else you must do to make fp.h work right). Alternatively, edit fp.h to suite your machine. If your system lacks /usr/include/fcntl.h , then you should simply create an empty fcntl.h in this directory. If your compiler then complains about creat and open not having a prototype, compile with OPEN_DECL defined. On many systems, open and creat are declared in fcntl.h . If your system's sprintf does not work the way ANSI C specifies -- specifically, if it does not return the number of characters transmitted -- then insert the line #define USE_STRLEN at the end of fmt.h . This is necessary with at least some versions of Sun software. In particular, if you get a warning about an improper pointer/integer combination in compiling wref.c, then you need to compile with -DUSE_STRLEN . If your system's fopen does not like the ANSI binary reading and writing modes "rb" and "wb", then you should compile open.c with NON_ANSI_RW_MODES #defined. If you get error messages about references to cf->_ptr and cf->_base when compiling wrtfmt.c and wsfe.c or to stderr->_flag when compiling err.c, then insert the line #define NON_UNIX_STDIO at the beginning of fio.h, and recompile everything (or at least those modules that contain NON_UNIX_STDIO). Unformatted sequential records consist of a length of record contents, the record contents themselves, and the length of record contents again (for backspace). Prior to 17 Oct. 1991, the length was of type int; now it is of type long, but you can change it back to int by inserting #define UIOLEN_int at the beginning of fio.h. This affects only sue.c and uio.c . 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. On VAX, Cray, or Research Tenth-Edition Unix systems, you may need to add -DVAX, -DCRAY, or -DV10 (respectively) to CFLAGS to make fp.h work correctly. Alternatively, you may need to edit fp.h to suit your machine. 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. You may need to supply the following non-ANSI routines: fstat(int fileds, struct stat *buf) is similar to stat(char *name, struct stat *buf), except that the first argument, fileds, is the file descriptor returned by open rather than the name of the file. fstat is used in the system-dependent routine canseek (in the libf2c source file err.c), which is supposed to return 1 if it's possible to issue seeks on the file in question, 0 if it's not; you may need to suitably modify err.c . On non-UNIX systems, you can avoid references to fstat and stat by compiling with NON_UNIX_STDIO defined; in that case, you may need to supply access(char *Name,0), which is supposed to return 0 if file Name exists, nonzero otherwise. char * mktemp(char *buf) is supposed to replace the 6 trailing X's in buf with a unique number and then return buf. The idea is to get a unique name for a temporary file. On non-UNIX systems, you may need to change a few other, e.g.: the form of name computed by mktemp() in endfile.c and open.c; the use of the open(), close(), and creat() system calls in endfile.c, err.c, open.c; and the modes in calls on fopen() and fdopen() (and perhaps the use of fdopen() itself -- it's supposed to return a FILE* corresponding to a given an integer file descriptor) in err.c and open.c (component ufmt of struct unit is 1 for formatted I/O -- text mode on some systems -- and 0 for unformatted I/O -- binary mode on some systems). Compiling with -DNON_UNIX_STDIO omits all references to creat() and almost all references to open() and close(), the exception being in the function f__isdev() (in open.c). If you wish to use translated Fortran that has funny notions of record length for direct unformatted I/O (i.e., that assumes RECL= values in OPEN statements are not bytes but rather counts of some other units -- e.g., 4-character words for VMS), then you should insert an appropriate #define for url_Adjust at the beginning of open.c . For VMS Fortran, for example, #define url_Adjust(x) x *= 4 would suffice. By default, Fortran I/O units 5, 6, and 0 are pre-connected to stdin, stdout, and stderr, respectively. You can change this behavior by changing f_init() in err.c to suit your needs. Note that f2c assumes READ(*... means READ(5... and WRITE(*... means WRITE(6... . Moreover, an OPEN(n,... statement that does not specify a file name (and does not specify STATUS='SCRATCH') assumes FILE='fort.n' . You can change this by editing open.c and endfile.c suitably. Unless you adjust the "#define MXUNIT" line in fio.h, Fortran units 0, 1, ..., 99 are available, i.e., the highest allowed unit number is MXUNIT - 1. Lines protected from compilation by #ifdef Allow_TYQUAD are for a possible extension to 64-bit integers in which integer = int = 32 bits and longint = long = 64 bits. 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 $(QINT) to the end of the makefile's dependency list for libf2c.a (if makefile is a copy of makefile.u; for the PC makefiles, add pow_qq.obj qbitbits.obj qbitshft.obj to the library's dependency list and adjust libf2c.lbc or libf2c.sy accordingly). Also add -DAllow_TYQUAD to the makefile's CFLAGS assignment. To make longint and ulongint available, it may suffice to add -DINTEGER_STAR_8 to the CFLAGS assignment. 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 . Extensions (Feb. 1993) to NAMELIST processing: 1. Reading a ? instead of &name (the start of a namelist) causes the namelist being sought to be written to stdout (unit 6); to omit this feature, compile rsne.c with -DNo_Namelist_Questions. 2. Reading the wrong namelist name now leads to an error message and an attempt to skip input until the right namelist name is found; to omit this feature, compile rsne.c with -DNo_Bad_Namelist_Skip. 3. Namelist writes now insert newlines before each variable; to omit this feature, compile xwsne.c with -DNo_Extra_Namelist_Newlines. 4. (Sept. 1995) When looking for the &name that starts namelist input, lines whose first non-blank character is something other than &, $, or ? are treated as comment lines and ignored, unless rsne.c is compiled with -DNo_Namelist_Comments. Nonstandard extension (Feb. 1993) to open: for sequential files, ACCESS='APPEND' (or access='anything else starting with "A" or "a"') causes the file to be positioned at end-of-file, so a write will append to the file. Some buggy Fortran programs use unformatted direct I/O to write an incomplete record and later read more from that record than they have written. For records other than the last, the unwritten portion of the record reads as binary zeros. The last record is a special case: attempting to read more from it than was written gives end-of-file -- which may help one find a bug. Some other Fortran I/O libraries treat the last record no differently than others and thus give no help in finding the bug of reading more than was written. If you wish to have this behavior, compile uio.c with -DPad_UDread . If you want to be able to catch write failures (e.g., due to a disk being full) with an ERR= specifier, compile dfe.c, due.c, sfe.c, sue.c, and wsle.c with -DALWAYS_FLUSH. This will lead to slower execution and more I/O, but should make ERR= work as expected, provided fflush returns an error return when its physical write fails. Carriage controls are meant to be interpreted by the UNIX col program (or a similar program). Sometimes it's convenient to use only ' ' as the carriage control character (normal single spacing). If you compile lwrite.c and wsfe.c with -DOMIT_BLANK_CC, formatted external output lines will have an initial ' ' quietly omitted, making use of the col program unnecessary with output that only has ' ' for carriage control. The Fortran 77 Standard leaves it up to the implementation whether formatted writes of floating-point numbers of absolute value < 1 have a zero before the decimal point. By default, libI77 omits such superfluous zeros, but you can cause them to appear by compiling lwrite.c, wref.c, and wrtfmt.c with -DWANT_LEAD_0 . If your (Unix) 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 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. Nowadays most Unix and Linux systems have function int ftruncate(int fildes, off_t len); defined in system header file unistd.h that adjusts the length of file descriptor fildes to length len. Unless endfile.c is compiled with -DNO_TRUNCATE, endfile.c #includes "unistd.h" and calls ftruncate() if necessary to shorten files. If your system lacks ftruncate(), compile endfile.c with -DNO_TRUNCATE to make endfile.c use the older and more portable scheme of shortening a file by copying to a temporary file and back again. 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.)