OPENSSL_API_COMPAT定义

NAME

openssl_user_macros, OPENSSL_API_COMPAT, OPENSSL_NO_DEPRECATED - User defined macros

DESCRIPTION

User defined macros allow the programmer to control certain aspects of what is exposed by the OpenSSL headers.

NOTE: to be effective, a user defined macro must be defined before including any header file that depends on it, either in the compilation command (cc -DMACRO=value) or by defining the macro in source before including any headers.

Other manual pages may refer to this page when declarations depend on user defined macros.

The macros

OPENSSL_API_COMPAT
The value is a version number, given in one of the following two forms:

0xMNNFF000L
This is the form supported for all versions up to 1.1.x, where M represents the major number, NN represents the minor number, and FF represents the fix number, as a hexadecimal number. For version 1.1.0, that’s 0x10100000L.

Any version number may be given, but these numbers are the current known major deprecation points, making them the most meaningful:

0x00908000L (version 0.9.8)
0x10000000L (version 1.0.0)
0x10100000L (version 1.1.0)
For convenience, higher numbers are accepted as well, as long as feasible. For example, 0x60000000L will work as expected. However, it is recommended to start using the second form instead:

mmnnpp
This form is a simple decimal number calculated with this formula:

major _ 10000 + minor _ 100 + patch

where major, minor and patch are the desired major, minor and patch components of the version number. For example:

30000 corresponds to version 3.0.0
10002 corresponds to version 1.0.2
420101 corresponds to version 42.1.1
If OPENSSL_API_COMPAT is undefined, this default value is used in its place: 30300

OPENSSL_NO_DEPRECATED
If this macro is defined, all deprecated public symbols in all OpenSSL versions up to and including the version given by OPENSSL_API_COMPAT (or the default value given above, when OPENSSL_API_COMPAT isn’t defined) will be hidden.

https://www.openssl.org/docs/manmaster/man7/OPENSSL_API_COMPAT.html