00549nam a22001697a 4500003000200000005001700002008004100019020001800060050002400078100002700102245005200129260005000181300004000231504005100271650003500322650002200357020240927073950.0240927b        xxu||||| |||| 00| 0 eng d  a9781632409874  aQA 76.77b.B37 2020  aBarnes, Reid,eauthor.  aUnderstanding operating systems /cReid Barnes.  aNew Yorl, NY :bClanrye International,c2020.  aviii, 243 p. :bcol. ill. ;c26 cm.  aIncludes bibliographical references and index.  aOperating systems (Computers).  aSystems software.