| Index Entry |  Section | 
 
  | 
| D |  |  | 
 | data, erasing | 11.6 shred: Remove files more securely | 
 | database for color setup, printing | 10.4 dircolors: Color setup for ls | 
 | date | 21.1 date: Print or set system date and time | 
 | date directives | 21.1.2 Date directives | 
 | date format, ISO 8601 | 27.2 Calendar date items | 
 | date input formats | 27. Date input formats | 
 | date options | 21.1.6 Options for date | 
 | date strings, parsing | 21.1.6 Options for date | 
 | day in date strings | 27.6 Relative items in date strings | 
 | day in date strings | 27.6 Relative items in date strings | 
 | day of week item | 27.5 Day of week items | 
 | dd | 11.2 dd: Convert and copy a file | 
 | dec | 19.2.5 Combination settings | 
 | decctlq | 19.2.5 Combination settings | 
 | delay for a specified time | 24.1 sleep: Delay for a specified time | 
 | delaying commands | 24. Delaying | 
 | deleting characters | 9.1.3 Squeezing repeats and deleting | 
 | dereferencing symbolic links | 12.2 ln: Make links between files | 
 | descriptor follow option | 5.2 tail: Output the last part of files | 
 | destination directory | 2.3 Target directory | 
 | destination directory | 11.1 cp: Copy files and directories | 
 | destination directory | 11.3 install: Copy files and set attributes | 
 | destination directory | 11.4 mv: Move (rename) files | 
 | destination directory | 12.2 ln: Make links between files | 
 | destinations, multiple output | 17.1 tee: Redirect output to multiple files | 
 | device file, disk | 14.1 df: Report filesystem disk space usage | 
 | df | 14.1 df: Report filesystem disk space usage | 
 | DF_BLOCK_SIZE | 2.2 Block size | 
 | dictionary order | 7.1 sort: Sort text files | 
 | differing lines | 7.3 comm: Compare two sorted files line by line | 
 | digit | 9.1.1 Specifying sets of characters | 
 | dir | 10.2 dir: Briefly list directory contents | 
 | dircolors | 10.4 dircolors: Color setup for ls | 
 | directives, date | 21.1.2 Date directives | 
 | directives, literal | 21.1.3 Literal directives | 
 | directives, time | 21.1.1 Time directives | 
 | directories, copying | 11.1 cp: Copy files and directories | 
 | directories, copying recursively | 11.1 cp: Copy files and directories | 
 | directories, copying recursively | 11.1 cp: Copy files and directories | 
 | directories, creating | 12.3 mkdir: Make directories | 
 | directories, creating with given attributes | 11.3 install: Copy files and set attributes | 
 | directories, removing (recursively) | 11.5 rm: Remove files or directories | 
 | directories, removing empty | 12.6 rmdir: Remove empty directories | 
 | directories, removing with unlink | 11.5 rm: Remove files or directories | 
 | directory check | 16.3.1 File type tests | 
 | directory components, printing | 18.2 dirname: Strip non-directory suffix from a file name | 
 | directory deletion, ignoring failures | 12.6 rmdir: Remove empty directories | 
 | directory deletion, reporting | 12.6 rmdir: Remove empty directories | 
 | directory listing | 10.1 ls: List directory contents | 
 | directory listing, brief | 10.2 dir: Briefly list directory contents | 
 | directory listing, recursive | 10.1.1 Which files are listed | 
 | directory listing, verbose | 10.3 vdir: Verbosely list directory contents | 
 | directory order, listing by | 10.1.3 Sorting the output | 
 | directory, stripping from file names | 18.1 basename: Strip directory and suffix from a file name | 
 | dired Emacs mode support | 10.1.2 What information is listed | 
 | dirname | 18.2 dirname: Strip non-directory suffix from a file name | 
 | disabling special characters | 19.2.6 Special characters | 
 | disk allocation | 10.1.2 What information is listed | 
 | disk device file | 14.1 df: Report filesystem disk space usage | 
 | disk usage | 14. Disk usage | 
 | disk usage by filesystem | 14.1 df: Report filesystem disk space usage | 
 | disk usage for files | 14.2 du: Estimate file space usage | 
 | diskette filesystem | 14.1 df: Report filesystem disk space usage | 
 | displacement of dates | 27.6 Relative items in date strings | 
 | displaying text | 15.1 echo: Print a line of text | 
 | division | 16.4.2 Numeric expressions | 
 | do nothing, successfully | 16.2 true: Do nothing, successfully | 
 | do nothing, unsuccessfully | 16.1 false: Do nothing, unsuccessfully | 
 | DOS filesystem | 14.1 df: Report filesystem disk space usage | 
 | double spacing | 4.2 pr: Paginate or columnate files for printing | 
 | down columns | 4.2 pr: Paginate or columnate files for printing | 
 | dsusp | 19.2.6 Special characters | 
 | du | 14.2 du: Estimate file space usage | 
 | DU_BLOCK_SIZE | 2.2 Block size | 
 | duplicate lines, outputting | 7.2 uniq: Uniquify files | 
 
  | 
| E |  |  | 
 | ebcdic, converting to | 11.2 dd: Convert and copy a file | 
 | echo | 19.2.4 Local settings | 
 | echoctl | 19.2.4 Local settings | 
 | echoe | 19.2.4 Local settings | 
 | echok | 19.2.4 Local settings | 
 | echoke | 19.2.4 Local settings | 
 | echonl | 19.2.4 Local settings | 
 | echoprt | 19.2.4 Local settings | 
 | effective uid and gid, printing | 20.1 id: Print real and effective uid and gid | 
 | effective UID, printing | 20.3 whoami: Print effective user id | 
 | efs filesystem type | 14.1 df: Report filesystem disk space usage | 
 | Eggert, Paul | 27.8 Authors of getdate | 
 | eight-bit characters | 19.2.1 Control settings | 
 | eight-bit characters | 19.2.5 Combination settings | 
 | eight-bit input | 19.2.2 Input settings | 
 | ek | 19.2.5 Combination settings | 
 | empty files, creating | 13.4 touch: Change file timestamps | 
 | empty lines, numbering | 3.3 nl: Number lines and write files | 
 | entire files, output of | 3. Output of entire files | 
 | env | 22.2 env: Run a command in a modified environment | 
 | environment variables, printing | 19.3 printenv: Print all or some environment variables | 
 | environment, preserving | 22.5 su: Run a command with substitute user and group id | 
 | environment, printing | 22.2 env: Run a command in a modified environment | 
 | environment, running a program in a modified | 22.2 env: Run a command in a modified environment | 
 | eof | 19.2.6 Special characters | 
 | eol | 19.2.6 Special characters | 
 | eol2 | 19.2.6 Special characters | 
 | epoch, for POSIX | 27. Date input formats | 
 | epoch, seconds since | 21.1.1 Time directives | 
 | equal string check | 16.3.4 String tests | 
 | equivalence classes | 9.1.1 Specifying sets of characters | 
 | erase | 19.2.6 Special characters | 
 | erasing data | 11.6 shred: Remove files more securely | 
 | error messages, omitting | 13.1 chown: Change file owner and group | 
 | error messages, omitting | 13.2 chgrp: Change group ownership | 
 | error messages, omitting | 13.3 chmod: Change access permissions | 
 | evaluation of expressions | 16.4 expr: Evaluate expressions | 
 | even parity | 19.2.1 Control settings | 
 | evenp | 19.2.5 Combination settings | 
 | exabyte, definition of | 2.2 Block size | 
 | examples of date | 21.1.7 Examples of date | 
 | examples of expr | 16.4.4 Examples of using expr | 
 | exbibyte, definition of | 2.2 Block size | 
 | excluding files from du | 14.2 du: Estimate file space usage | 
 | excluding files from du | 14.2 du: Estimate file space usage | 
 | executable file check | 16.3.2 Access permission tests | 
 | executables and file type, marking | 10.1.5 General output formatting | 
 | execute permission | 26.1 Structure of File Permissions | 
 | execute permission, symbolic | 26.2.1 Setting Permissions | 
 | existence-of-file check | 16.3.3 File characteristic tests | 
 | existing backup method | 2.1 Backup options | 
 | exit status commands | 16. Conditions | 
 | exit status of expr | 16.4 expr: Evaluate expressions | 
 | exit status of false | 16.1 false: Do nothing, unsuccessfully | 
 | exit status of nohup | 22.4 nohup: Run a command immune to hangups | 
 | exit status of pathchk | 18.3 pathchk: Check file name portability | 
 | exit status of printenv | 19.3 printenv: Print all or some environment variables | 
 | exit status of true | 16.2 true: Do nothing, successfully | 
 | exit status of tty | 19.4 tty: Print file name of terminal on standard input | 
 | expand | 9.2 expand: Convert tabs to spaces | 
 | expr | 16.4 expr: Evaluate expressions | 
 | expression evaluation | 16.3 test: Check file types and compare values | 
 | expression evaluation | 16.4 expr: Evaluate expressions | 
 | expressions, numeric | 16.4.2 Numeric expressions | 
 | expressions, string | 16.4.1 String expressions | 
 | extension, sorting files by | 10.1.3 Sorting the output | 
 
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