Found the code, and it's actually part of python (as of 2.4). Gentoo sets aliased to 1 when printing the system uname. /usr/lib/python2.{4,5,6}/platform.py:
def _platform(*args): """ Helper to format the platform string in a filename compatible format e.g. "system-version-machine". """ # Format the platform string platform = string.join( map(string.strip, filter(len,args)), '-') # Cleanup some possible filename obstacles... replace = string.replace platform = replace(platform,' ','_') platform = replace(platform,'/','-') platform = replace(platform,'\\','-') platform = replace(platform,':','-') platform = replace(platform,';','-') platform = replace(platform,'"','-') platform = replace(platform,'(','-') platform = replace(platform,')','-') # No need to report 'unknown' information... platform = replace(platform,'unknown','') # Fold '--'s and remove trailing '-' while 1: cleaned = replace(platform,'--','-') if cleaned == platform: break platform = cleaned while platform[-1] == '-': platform = platform[:-1] return platform def platform(aliased=0, terse=0): """ Returns a single string identifying the underlying platform with as much useful information as possible (but no more :). The output is intended to be human readable rather than machine parseable. It may look different on different platforms and this is intended. If "aliased" is true, the function will use aliases for various platforms that report system names which differ from their common names, e.g. SunOS will be reported as Solaris. The system_alias() function is used to implement this. Setting terse to true causes the function to return only the absolute minimum information needed to identify the platform. """ result = _platform_cache.get((aliased, terse), None) if result is not None: return result # Get uname information and then apply platform specific cosmetics # to it... system,node,release,version,machine,processor = uname() if machine == processor: processor = '' if aliased: system,release,version = system_alias(system,release,version) if system == 'Windows': # MS platforms rel,vers,csd,ptype = win32_ver(version) if terse: platform = _platform(system,release) else: platform = _platform(system,release,version,csd) elif system in ('Linux',): # Linux based systems distname,distversion,distid = dist('') if distname and not terse: platform = _platform(system,release,machine,processor, 'with', distname,distversion,distid) else: # If the distribution name is unknown check for libc vs. glibc libcname,libcversion = libc_ver(sys.executable) platform = _platform(system,release,machine,processor, 'with', libcname+libcversion) elif system == 'Java': # Java platforms r,v,vminfo,(os_name,os_version,os_arch) = java_ver() if terse: platform = _platform(system,release,version) else: platform = _platform(system,release,version, 'on', os_name,os_version,os_arch) elif system == 'MacOS': # MacOS platforms if terse: platform = _platform(system,release) else: platform = _platform(system,release,machine) else: # Generic handler if terse: platform = _platform(system,release) else: bits,linkage = architecture(sys.executable) platform = _platform(system,release,machine,processor,bits,linkage) _platform_cache[(aliased, terse)] = platform return platform Proof: run /usr/lib/python2.{4,5,6}/platform.py aliased and terse have no effect wrt output (kernel_version-with-libc_version) -- Andrey Vul A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?