2.6.1: AC_CHECK_HEADERS(sys/sysctl.h)

[Christian Weisgerber]

2.6.1's configure script checks for the <sys/sysctl.h> header file,
which elicits these warnings on OpenBSD:

checking sys/sysctl.h usability... no
checking sys/sysctl.h presence... yes
configure: WARNING: sys/sysctl.h: present but cannot be compiled
configure: WARNING: sys/sysctl.h:     check for missing prerequisite headers?
configure: WARNING: sys/sysctl.h: see the Autoconf documentation
configure: WARNING: sys/sysctl.h:     section "Present But Cannot Be Compiled"
configure: WARNING: sys/sysctl.h: proceeding with the preprocessor's result
configure: WARNING: sys/sysctl.h: in the future, the compiler will take precedence
configure: WARNING:     ## ------------------------------------------ ##
configure: WARNING:     ## Report this to the AC_PACKAGE_NAME lists.  ##
configure: WARNING:     ## ------------------------------------------ ##
checking for sys/sysctl.h... yes

The missing prerequisite header is <sys/param.h>.  However, it turns
out sysctl.h (HAVE_SYS_SYSCTL_H) isn't used anywhere in the rsync
code, so there's no point to check for this header in the first
place.

-- 
Christian "naddy" Weisgerber                          naddy at mips.inka.de