Check the CC and CFLAGS lines in the makefile

If your C library does not support the times(3) function, change the
#define TIMES to
#undef TIMES in speed.c
If it does, check the HZ value for the times(3) function.
If your system does not define CLK_TCK it will be assumed to
be 100.0.

If possible use gcc v 2.7.?
Turn on the maximum optimising (normally '-O3 -fomit-frame-pointer' for gcc)

type 'make'

run './destest' to check things are ok.
run './rpw' to check the tty code for reading passwords works.
run './speed' to see how fast those optimisations make the library run :-)

A make install will by default install
libdes.a      in /usr/local/lib/libdes.a
des           in /usr/local/bin/des
des_crypt.man in /usr/local/man/man3/des_crypt.3
des.man       in /usr/local/man/man1/des.1
des.h         in /usr/include/des.h

des(1) should be compatible with sunOS's but I have been unable to
test it.

These routines should compile on MSDOS, most 32bit and 64bit version
of Unix (BSD and SYSV) and VMS, without modification.
The only problems should be #include files that are in the wrong places.

These routines can be compiled under MSDOS.
I have successfully encrypted files using des(1) under MSDOS and then
decrypted the files on a SparcStation.
I have been able to compile and test the routines with
Microsoft C v 5.1 and Turbo C v 2.0.
The code in this library is in no way optimised for the 16bit
operation of MSDOS.  Microsoft C generates code that is 40% slower
than Turbo C's code.  I believe this is due to problems it has with
code generation with the 32bit shift operation in the IP and FP
sections.  I have added some 16bit optimization in ecb_encrypt.c
and this generated a %70 speedup under Turbo C.  Such are the
limitations of DOS compilers :-(.

For Turbo C v 2.0, make sure to define MSDOS, in the relevant menu.

There is an alternative version of the D_ENCRYPT macro that can be
enabled with the -DDES_USE_PTR option in the makefile.  This alternative
macro can make a +-%20 speed difference to the DES encryption speed,
depending on the compiler/CPU combinations.
It has its greatest effect on Sparc machines when using the sun compiler.
If in doubt, try enable/disable it and running speed.  It does not
seem to affect gcc much.

When building for glibc, ignore all of the above and just unpack into
glibc-1.??/des and then gmake as per normal.