title: OS X or home-brew? How do I check
body: <p>Seems like someone is playing a prank on me. My computer settings change between days and I'm certain that this version is a home-brew and not the original OS X.</p>
  
  <p>Recovery/re-installation doesn't work because it restores itself after a day. How do I check if this is the original operating system?</p>
  
  <p>messing around with the terminal raises a few red flags. For example:</p>
  
  <p>master.passwd contains this:</p>
  
  <pre><code>nobody:*:-2:-2::0:0:Unprivileged User:/var/empty:/usr/bin/false
  root:*:0:0::0:0:System Administrator:/var/root:/bin/sh
  daemon:*:1:1::0:0:System Services:/var/root:/usr/bin/false
  _uucp:*:4:4::0:0:Unix to Unix Copy Protocol:/var/spool/uucp:/usr/sbin/uucico
  _taskgated:*:13:13::0:0:Task Gate Daemon:/var/empty:/usr/bin/false
  _networkd:*:24:24::0:0:Network Services:/var/networkd:/usr/bin/false
  _installassistant:*:25:25::0:0:Install Assistant:/var/empty:/usr/bin/false
  _lp:*:26:26::0:0:Printing Services:/var/spool/cups:/usr/bin/false
  _postfix:*:27:27::0:0:Postfix Mail Server:/var/spool/postfix:/usr/bin/false
  _scsd:*:31:31::0:0:Service Configuration Service:/var/empty:/usr/bin/false
  _ces:*:32:32::0:0:Certificate Enrollment Service:/var/empty:/usr/bin/false
  _appstore:*:33:33::0:0:Mac App Store Service:/var/empty:/usr/bin/false
  _mcxalr:*:54:54::0:0:MCX AppLaunch:/var/empty:/usr/bin/false
  _appleevents:*:55:55::0:0:AppleEvents Daemon:/var/empty:/usr/bin/false
  _geod:*:56:56::0:0:Geo Services Daemon:/var/db/geod:/usr/bin/false
  _devdocs:*:59:59::0:0:Developer Documentation:/var/empty:/usr/bin/false
  _sandbox:*:60:60::0:0:Seatbelt:/var/empty:/usr/bin/false
  _mdnsresponder:*:65:65::0:0:mDNSResponder:/var/empty:/usr/bin/false
  _ard:*:67:67::0:0:Apple Remote Desktop:/var/empty:/usr/bin/false
  _www:*:70:70::0:0:World Wide Web Server:/Library/WebServer:/usr/bin/false
  _eppc:*:71:71::0:0:Apple Events User:/var/empty:/usr/bin/false
  _cvs:*:72:72::0:0:CVS Server:/var/empty:/usr/bin/false
  _svn:*:73:73::0:0:SVN Server:/var/empty:/usr/bin/false
  _mysql:*:74:74::0:0:MySQL Server:/var/empty:/usr/bin/false
  _sshd:*:75:75::0:0:sshd Privilege separation:/var/empty:/usr/bin/false
  _qtss:*:76:76::0:0:QuickTime Streaming Server:/var/empty:/usr/bin/false
  _cyrus:*:77:6::0:0:Cyrus Administrator:/var/imap:/usr/bin/false
  _mailman:*:78:78::0:0:Mailman List Server:/var/empty:/usr/bin/false
  _appserver:*:79:79::0:0:Application Server:/var/empty:/usr/bin/false
  _clamav:*:82:82::0:0:ClamAV Daemon:/var/virusmails:/usr/bin/false
  _amavisd:*:83:83::0:0:AMaViS Daemon:/var/virusmails:/usr/bin/false
  _jabber:*:84:84::0:0:Jabber XMPP Server:/var/empty:/usr/bin/false
  _appowner:*:87:87::0:0:Application Owner:/var/empty:/usr/bin/false
  _windowserver:*:88:88::0:0:WindowServer:/var/empty:/usr/bin/false
  _spotlight:*:89:89::0:0:Spotlight:/var/empty:/usr/bin/false
  _tokend:*:91:91::0:0:Token Daemon:/var/empty:/usr/bin/false
  _securityagent:*:92:92::0:0:SecurityAgent:/var/db/securityagent:/usr/bin/false
  _calendar:*:93:93::0:0:Calendar:/var/empty:/usr/bin/false
  _teamsserver:*:94:94::0:0:TeamsServer:/var/teamsserver:/usr/bin/false
  _update_sharing:*:95:-2::0:0:Update Sharing:/var/empty:/usr/bin/false
  _installer:*:96:-2::0:0:Installer:/var/empty:/usr/bin/false
  _atsserver:*:97:97::0:0:ATS Server:/var/empty:/usr/bin/false
  _ftp:*:98:-2::0:0:FTP Daemon:/var/empty:/usr/bin/false
  _unknown:*:99:99::0:0:Unknown User:/var/empty:/usr/bin/false
  _softwareupdate:*:200:200::0:0:Software Update Service:/var/db/softwareupdate:/usr/bin/false
  _coreaudiod:*:202:202::0:0:Core Audio Daemon:/var/empty:/usr/bin/false
  _screensaver:*:203:203::0:0:Screensaver:/var/empty:/usr/bin/false
  _locationd:*:205:205::0:0:Location Daemon:/var/db/locationd:/usr/bin/false
  _trustevaluationagent:*:208:208::0:0:Trust Evaluation Agent:/var/empty:/usr/bin/false
  _timezone:*:210:210::0:0:AutoTimeZoneDaemon:/var/empty:/usr/bin/false
  _lda:*:211:211::0:0:Local Delivery Agent:/var/empty:/usr/bin/false
  _cvmsroot:*:212:212::0:0:CVMS Root:/var/empty:/usr/bin/false
  _usbmuxd:*:213:213::0:0:iPhone OS Device Helper:/var/db/lockdown:/usr/bin/false
  _dovecot:*:214:6::0:0:Dovecot Administrator:/var/empty:/usr/bin/false
  _dpaudio:*:215:215::0:0:DP Audio:/var/empty:/usr/bin/false
  _postgres:*:216:216::0:0:PostgreSQL Server:/var/empty:/usr/bin/false
  _krbtgt:*:217:-2::0:0:Kerberos Ticket Granting Ticket:/var/empty:/usr/bin/false
  _kadmin_admin:*:218:-2::0:0:Kerberos Admin Service:/var/empty:/usr/bin/false
  _kadmin_changepw:*:219:-2::0:0:Kerberos Change Password Service:/var/empty:/usr/bin/false
  </code></pre>
  
  <p>expected a command to set a master password...</p>