a.out(5) a.out: assembler and link editor output. acct(5) acct: execution accounting file. ar(5) ar: archive (library) file format. core(5) core: format of memory image file. dir(5) dir: format of directories. dump(5) dump, ddate: incremental dump format. environ(5) environ: user environment. filsys(5) filsys, flblk, ino: format of file system volume. group(5) group: group file. mpxio(5) mpxio: multiplexed i/o. mtab(5) mtab: mounted file system table. passwd(5) passwd: password file. plot(5) plot: graphics interface. tp(5) tp: DEC/mag tape formats. ttys(5) ttys: terminal initialization data. types(5) types: primitive system data types. utmp(5) utmp, wtmp: login records. wtmp(5) wtmp: user login history.