The distribution may choose not to support _XOPEN_CRYPT in the case that the distribution has transitioned from glibc crypt to libxcrypt. Signed-off-by: Carlos O'Donell <carlos@xxxxxxxxxx> -- Cheers, Carlos.
>From d099bd9550d28da19dd082d27491f49bd8c721e9 Mon Sep 17 00:00:00 2001 From: Carlos O'Donell <carlos@xxxxxxxxxxxxxxxx> Date: Thu, 12 Apr 2018 13:58:27 -0500 Subject: [PATCH 2/2] crypt.3, encrypt.3: Add notes about _XOPEN_CRYPT. The distribution may choose not to support _XOPEN_CRYPT in the case that the distribution has transitioned from glibc crypt to libxcrypt. Signed-off-by: Carlos O'Donell <carlos@xxxxxxxxxx> --- man3/crypt.3 | 22 ++++++++++++++++++++-- man3/encrypt.3 | 19 +++++++++++++++++++ 2 files changed, 39 insertions(+), 2 deletions(-) diff --git a/man3/crypt.3 b/man3/crypt.3 index 3e6552ad8..58c62d93d 100644 --- a/man3/crypt.3 +++ b/man3/crypt.3 @@ -188,8 +188,26 @@ POSIX.1-2001, POSIX.1-2008, SVr4, 4.3BSD. .BR crypt_r () is a GNU extension. .SH NOTES -.SS Glibc notes -The glibc2 version of this function supports additional +.SS Availability in glibc +The +.BR crypt (), +.BR encrypt (), +and +.BR setkey () +functions are part of the POSIX.1-2008 XSI Options Group for Encryption +and are optional. If the interfaces are not available then the symbolic +constant +.BR _XOPEN_CRYPT +is either not defined or defined to -1, and can be checked at runtime with +.BR sysconf (). +This may be the case if the downstream distribution has switched from glibc +crypt to libxcrypt. When recompiling applications in such distributions the +user must detect if +.BR _XOPEN_CRPYT +is not available and include crypt.h for the function prototypes; otherwise +libxcrypt is a ABI compatible drop-in replacement. +.SS Features in glibc +The glibc version of this function supports additional encryption algorithms. .PP If diff --git a/man3/encrypt.3 b/man3/encrypt.3 index 3a1cf9598..3df4870c3 100644 --- a/man3/encrypt.3 +++ b/man3/encrypt.3 @@ -147,6 +147,25 @@ and .BR setkey_r () are GNU extensions. .SH NOTES +.SS Availability in glibc +The +.BR crypt (), +.BR encrypt (), +and +.BR setkey () +functions are part of the POSIX.1-2008 XSI Options Group for Encryption +and are optional. If the interfaces are not available then the symbolic +constant +.BR _XOPEN_CRYPT +is either not defined or defined to -1, and can be checked at runtime with +.BR sysconf (). +This may be the case if the downstream distribution has switched from glibc +crypt to libxcrypt. When recompiling applications in such distributions the +user must detect if +.BR _XOPEN_CRPYT +is not available and include crypt.h for the function prototypes; otherwise +libxcrypt is a ABI compatible drop-in replacement. +.SS Features in glibc In glibc 2.2, these functions use the DES algorithm. .SH EXAMPLE .EX -- 2.14.3
