Gets information about the system.
Posix requires that assumptions must not be made about the format of the values, e.g. the assumption that a release may contain three digits or anything else returned by this function.
This function has no parameters.
Returns a hash of strings with information about the system. The indices of the hash are
sysname - operating system name (e.g. Linux)
nodename - system name (e.g. valiant)
release - operating system release (e.g. 2.2.10)
version - operating system version (e.g. #4 Tue Jul 20 17:01:36 MEST 1999)
machine - system architecture (e.g. i586)
domainname - DNS domainname (e.g. example.com)
domainname is a GNU extension and not part of POSIX.1, so this field is only available on GNU systems or when using the GNU libc.
The function returns false on failure.