Initial revision

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@171 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/des/INSTALL

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+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 60.
+
+If possible use gcc v 2.2.2
+Turn on the maximum optimising
+
+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 -DALT_ECB 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.