+ des, dh, dsa, ecdh, ecdsa, idea, md4, mdc2, ocb, poly1305,
+ rc2, rc4, rmd160, scrypt, seed, siphash, sm3, sm4 or
+ whirlpool. The "ripemd" algorithm is deprecated and if used
+ is synonymous with rmd160.
+
+ -Dxxx, -Ixxx, -Wp, -lxxx, -Lxxx, -Wl, -rpath, -R, -framework, -static
+ These system specific options will be recognised and
+ passed through to the compiler to allow you to define
+ preprocessor symbols, specify additional libraries, library
+ directories or other compiler options. It might be worth
+ noting that some compilers generate code specifically for
+ processor the compiler currently executes on. This is not
+ necessarily what you might have in mind, since it might be
+ unsuitable for execution on other, typically older,
+ processor. Consult your compiler documentation.
+
+ Take note of the VAR=value documentation below and how
+ these flags interact with those variables.
+
+ -xxx, +xxx
+ Additional options that are not otherwise recognised are
+ passed through as they are to the compiler as well. Again,
+ consult your compiler documentation.
+
+ Take note of the VAR=value documentation below and how
+ these flags interact with those variables.
+
+ VAR=value
+ Assignment if environment variable for Configure. These
+ work just like normal environment variable assignments,
+ but are supported on all platforms and are confined to
+ the configuration scripts only. These assignments override
+ the corresponding value in the inherited environment, if
+ there is one.
+
+ The following variables are used as "make variables" and
+ can be used as an alternative to giving preprocessor,
+ compiler and linker options directly as configuration.
+ The following variables are supported:
+
+ AR The static library archiver.
+ ARFLAGS Flags for the static library archiver.
+ AS The assembler compiler.
+ ASFLAGS Flags for the assembler compiler.
+ CC The C compiler.
+ CFLAGS Flags for the C compiler.
+ CXX The C++ compiler.
+ CXXFLAGS Flags for the C++ compiler.
+ CPP The C/C++ preprocessor.
+ CPPFLAGS Flags for the C/C++ preprocessor.
+ CPPDEFINES List of CPP macro definitions, separated
+ by a platform specific character (':' or
+ space for Unix, ';' for Windows, ',' for
+ VMS). This can be used in place of -D.
+ CPPINCLUDES List of CPP inclusion directories, separated
+ the same way as for CPPDEFINES. This can
+ be used in place of -I.
+ HASHBANGPERL Perl invocation to be inserted after '#!'
+ in public perl scripts.
+ LD The program linker (not used on Unix, $(CC)
+ is used there).
+ LDFLAGS Flags for the shared library, DSO and
+ program linker.
+ LDLIBS Extra libraries to use when linking.
+ Takes the form of a space separated list
+ of library specifications on Unix and
+ Windows, and as a comma separated list of
+ libraries on VMS.
+ RANLIB The library archive indexer.
+ RC The Windows resources manipulator.
+ RCFLAGS Flags for the Windows reources manipulator.
+ RM The command to remove files and directories.
+
+ These can be mixed with flags given on the command line.
+ Any variable assignment resets any corresponding flags
+ given before it, so for example:
+
+ ./config -DFOO CPPFLAGS=-DBAR -DCOOKIE
+
+ Will end up having 'CPPFLAGS=-DBAR -DCOOKIE'.
+
+ Here is how the flags documented above are collected as
+ augmentation of these variables:
+
+ -Dxxx xxx is collected in CPPDEFINES
+ -Ixxx xxx is collected in CPPINCLUDES
+ -Wp,xxx collected in CPPFLAGS
+ -Lxxx collected in LDFLAGS
+ -lxxx collected in LDLIBS
+ -Wp,xxx collected in LDLIBS
+ -rpath xxx collected in LDLIBS
+ -R xxx collected in LDLIBS
+ -framework xxx collected in LDLIBS
+ -static collected in LDLIBS
+ -xxx collected in CFLAGS
+ +xxx collected in CFLAGS
+
+ reconf
+ reconfigure
+ Reconfigure from earlier data. This fetches the previous
+ command line options and environment from data saved in
+ "configdata.pm", and runs the configuration process again,
+ using these options and environment.
+ Note: NO other option is permitted together with "reconf".
+ This means that you also MUST use "./Configure" (or
+ what corresponds to that on non-Unix platforms) directly
+ to invoke this option.
+ Note: The original configuration saves away values for ALL
+ environment variables that were used, and if they weren't
+ defined, they are still saved away with information that
+ they weren't originally defined. This information takes
+ precedence over environment variables that are defined
+ when reconfiguring.
+
+ Displaying configuration data
+ -----------------------------
+
+ The configuration script itself will say very little, and finishes by
+ creating "configdata.pm". This perl module can be loaded by other scripts
+ to find all the configuration data, and it can also be used as a script to
+ display all sorts of configuration data in a human readable form.
+
+ For more information, please do:
+
+ $ ./configdata.pm --help # Unix