\chapentry {Introduction}{1}{1} \chapentry {Common options}{2}{2} \secentry {Backup options}{2}{1}{2} \chapentry {File permissions}{3}{3} \secentry {Structure of File Permissions}{3}{1}{3} \secentry {Symbolic Modes}{3}{2}{3} \subsecentry {Setting Permissions}{3}{2}{1}{4} \subsecentry {Copying Existing Permissions}{3}{2}{2}{5} \subsecentry {Changing Special Permissions}{3}{2}{3}{5} \subsecentry {Conditional Executability}{3}{2}{4}{6} \subsecentry {Making Multiple Changes}{3}{2}{5}{6} \subsecentry {The Umask and Protection}{3}{2}{6}{7} \secentry {Numeric Modes}{3}{3}{7} \chapentry {Date input formats}{4}{9} \secentry {General date syntax}{4}{1}{9} \secentry {Calendar date item}{4}{2}{10} \secentry {Time of day item}{4}{3}{11} \secentry {Timezone item}{4}{4}{11} \secentry {Day of week item}{4}{5}{13} \secentry {Relative item in date strings}{4}{6}{13} \secentry {Pure numbers in date strings}{4}{7}{13} \secentry {Authors of \code {getdate}}{4}{8}{14} \chapentry {Directory listing}{5}{15} \secentry {\code {ls}: List directory contents}{5}{1}{15} \subsecentry {Which files are listed}{5}{1}{1}{15} \subsecentry {What information is listed}{5}{1}{2}{16} \subsecentry {Sorting the output}{5}{1}{3}{17} \subsecentry {General output formatting}{5}{1}{4}{18} \subsecentry {Formatting the file names}{5}{1}{5}{20} \secentry {\code {dir}: Briefly list directory contents}{5}{2}{20} \secentry {\code {vdir}: Verbosely list directory contents}{5}{3}{20} \secentry {\code {dircolors}: Color setup for \code {ls}}{5}{4}{20} \chapentry {Basic operations}{6}{22} \secentry {\code {cp}: Copy files and directories}{6}{1}{22} \secentry {\code {dd}: Convert and copy a file}{6}{2}{24} \secentry {\code {install}: Copy files and set attributes}{6}{3}{25} \secentry {\code {mv}: Move (rename) files}{6}{4}{27} \secentry {\code {rm}: Remove files or directories}{6}{5}{28} \chapentry {Special file types}{7}{29} \secentry {\code {ln}: Make links between files}{7}{1}{29} \secentry {\code {mkdir}: Make directories}{7}{2}{30} \secentry {\code {mkfifo}: Make FIFOs (named pipes)}{7}{3}{31} \secentry {\code {mknod}: Make block or character special files}{7}{4}{31} \secentry {\code {rmdir}: Remove empty directories}{7}{5}{32} \chapentry {Changing file attributes}{8}{33} \secentry {\code {chown}: Change file owner and group}{8}{1}{33} \secentry {\code {chgrp}: Change group ownership}{8}{2}{34} \secentry {\code {chmod}: Change access permissions}{8}{3}{34} \secentry {\code {touch}: Change file timestamps}{8}{4}{35} \chapentry {Disk usage}{9}{37} \secentry {\code {df}: Report filesystem disk space usage}{9}{1}{37} \secentry {\code {du}: Estimate file space usage}{9}{2}{39} \secentry {\code {sync}: Synchronize data on disk with memory}{9}{3}{40} \unnumbchapentry {Index}{41} .