coreutils.texi

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\input texinfo
@c %**start of header
@setfilename coreutils.info
@settitle @sc{gnu} Core-utils

@c %**end of header

@include version.texi
@include constants.texi

@c Define new indices.
@defcodeindex op
@defcodeindex fl

@c Put everything in one index (arbitrarily chosen to be the concept index).
@syncodeindex fl cp
@syncodeindex fn cp
@syncodeindex ky cp
@syncodeindex op cp
@syncodeindex pg cp
@syncodeindex vr cp

@ifinfo
@format
START-INFO-DIR-ENTRY
* @sc{gnu} Utilities: (coreutils).              @sc{gnu} Utilities.
* Common options: (coreutils)Common options.    Common options.
* File permissions: (coreutils)File permission. Access modes.
* Date input formats: (coreutils)Date input formats.

* basename: (coreutils)basename invocation.     Strip directory and suffix.
* cat: (coreutils)cat invocation.               Concatenate and write files.
* chgrp: (coreutils)chgrp invocation.           Change file groups.
* chmod: (coreutils)chmod invocation.           Change file permissions.
* chown: (coreutils)chown invocation.           Change file owners/groups.
* chroot: (coreutils)chroot invocation.         Specify the root directory.
* cksum: (coreutils)cksum invocation.           Print @acronym{POSIX} CRC checksum.
* comm: (coreutils)comm invocation.             Compare sorted files by line.
* cp: (coreutils)cp invocation.                 Copy files.
* csplit: (coreutils)csplit invocation.         Split by context.
* cut: (coreutils)cut invocation.               Print selected parts of lines.
* date: (coreutils)date invocation.             Print/set system date and time.
* dd: (coreutils)dd invocation.                 Copy and convert a file.
* df: (coreutils)df invocation.                 Report filesystem disk usage.
* dir: (coreutils)dir invocation.               List directories briefly.
* dircolors: (coreutils)dircolors invocation.   Color setup for ls.
* dirname: (coreutils)dirname invocation.       Strip non-directory suffix.
* du: (coreutils)du invocation.                 Report on disk usage.
* echo: (coreutils)echo invocation.             Print a line of text.
* env: (coreutils)env invocation.               Modify the environment.
* expand: (coreutils)expand invocation.         Convert tabs to spaces.
* expr: (coreutils)expr invocation.             Evaluate expressions.
* factor: (coreutils)factor invocation.         Print prime factors
* false: (coreutils)false invocation.           Do nothing, unsuccessfully.
* fmt: (coreutils)fmt invocation.               Reformat paragraph text.
* fold: (coreutils)fold invocation.             Wrap long input lines.
* groups: (coreutils)groups invocation.         Print group names a user is in.
* head: (coreutils)head invocation.             Output the first part of files.
* hostid: (coreutils)hostid invocation.         Print numeric host identifier.
* hostname: (coreutils)hostname invocation.     Print or set system name.
* id: (coreutils)id invocation.                 Print real/effective uid/gid.
* install: (coreutils)install invocation.       Copy and change attributes.
* join: (coreutils)join invocation.             Join lines on a common field.
* kill: (coreutils)kill invocation.             Send a signal to processes.
* link: (coreutils)link invocation.             Make hard links between files.
* ln: (coreutils)ln invocation.                 Make links between files.
* logname: (coreutils)logname invocation.       Print current login name.
* ls: (coreutils)ls invocation.                 List directory contents.
* md5sum: (coreutils)md5sum invocation.         Print or check message-digests.
* mkdir: (coreutils)mkdir invocation.           Create directories.
* mkfifo: (coreutils)mkfifo invocation.         Create FIFOs (named pipes).
* mknod: (coreutils)mknod invocation.           Create special files.
* mv: (coreutils)mv invocation.                 Rename files.
* nice: (coreutils)nice invocation.             Modify scheduling priority.
* nl: (coreutils)nl invocation.                 Number lines and write files.
* nohup: (coreutils)nohup invocation.           Immunize to hangups.
* od: (coreutils)od invocation.                 Dump files in octal, etc.
* paste: (coreutils)paste invocation.           Merge lines of files.
* pathchk: (coreutils)pathchk invocation.       Check file name portability.
* pr: (coreutils)pr invocation.                 Paginate or columnate files.
* printenv: (coreutils)printenv invocation.     Print environment variables.
* printf: (coreutils)printf invocation.         Format and print data.
* ptx: (coreutils)ptx invocation.               Produce permuted indexes.
* pwd: (coreutils)pwd invocation.               Print working directory.
* rm: (coreutils)rm invocation.                 Remove files.
* rmdir: (coreutils)rmdir invocation.           Remove empty directories.
* seq: (coreutils)seq invocation.               Print numeric sequences
* shred: (coreutils)shred invocation.           Remove files more securely.
* sleep: (coreutils)sleep invocation.           Delay for a specified time.
* sort: (coreutils)sort invocation.             Sort text files.
* split: (coreutils)split invocation.           Split into fixed-size pieces.
* stat: (coreutils)stat invocation.             Report file or filesystem status.
* stty: (coreutils)stty invocation.             Print/change terminal settings.
* su: (coreutils)su invocation.                 Modify user and group id.
* sum: (coreutils)sum invocation.               Print traditional checksum.
* sync: (coreutils)sync invocation.             Synchronize memory and disk.
* tac: (coreutils)tac invocation.               Reverse files.
* tail: (coreutils)tail invocation.             Output the last part of files.
* tee: (coreutils)tee invocation.               Redirect to multiple files.
* test: (coreutils)test invocation.             File/string tests.
* touch: (coreutils)touch invocation.           Change file timestamps.
* tr: (coreutils)tr invocation.                 Translate characters.
* true: (coreutils)true invocation.             Do nothing, successfully.
* tsort: (coreutils)tsort invocation.           Topological sort.
* tty: (coreutils)tty invocation.               Print terminal name.
* uname: (coreutils)uname invocation.           Print system information.
* unexpand: (coreutils)unexpand invocation.     Convert spaces to tabs.
* unlink: (coreutils)unlink invocation.         Remove files via unlink syscall.
* uniq: (coreutils)uniq invocation.             Uniquify files.
* users: (coreutils)users invocation.           Print current user names.
* vdir: (coreutils)vdir invocation.             List directories verbosely.
* wc: (coreutils)wc invocation.                 Byte, word, and line counts.
* who: (coreutils)who invocation.               Print who is logged in.
* whoami: (coreutils)whoami invocation.         Print effective user id.
* yes: (coreutils)yes invocation.               Print a string indefinitely.
END-INFO-DIR-ENTRY
@end format
@end ifinfo

@copying
This manual documents version @value{VERSION} of the @sc{gnu} command
line utilities.

Copyright @copyright{} 1994, 1995, 1996, 2000, 2001, 2002
Free Software Foundation, Inc.

@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
Texts.  A copy of the license is included in the section entitled ``GNU
Free Documentation License''.
@end quotation
@end copying

@titlepage
@title @sc{gnu} @code{Core-utils}
@subtitle A set of command line utilities
@subtitle for version @value{VERSION}, @value{UPDATED}
@author David MacKenzie et al.

@page
@vskip 0pt plus 1filll
@insertcopying
@end titlepage


@c If your makeinfo doesn't grok this @ifnottex directive, then either
@c get a newer version of makeinfo or do s/ifnottex/ifinfo/ here and on
@c the matching @end directive below.
@ifnottex
@node Top
@top GNU Core-utils

@insertcopying
@end ifnottex

@cindex text utilities
@cindex shell utilities
@cindex file utilities

@menu
* Introduction::                       Caveats, overview, and authors.
* Common options::                     Common options.
* Output of entire files::             cat tac nl od
* Formatting file contents::           fmt pr fold
* Output of parts of files::           head tail split csplit
* Summarizing files::                  wc sum cksum md5sum
* Operating on sorted files::          sort uniq comm ptx tsort
* Operating on fields within a line::  cut paste join
* Operating on characters::            tr expand unexpand
* Directory listing::                  ls dir vdir d v dircolors
* Basic operations::                   cp dd install mv rm shred
* Special file types::                 ln mkdir rmdir mkfifo mknod
* Changing file attributes::           chgrp chmod chown touch
* Disk usage::                         df du stat sync
* Printing text::                      echo printf yes
* Conditions::                         false true test expr
* Redirection::                        tee
* File name manipulation::             dirname basename pathchk
* Working context::                    pwd stty printenv tty
* User information::                   id logname whoami groups users who
* System context::                     date uname hostname
* Modified command invocation::        chroot env nice nohup su
* Process control::                    kill
* Delaying::                           sleep
* Numeric operations::                 factor seq
* File permissions::                   Access modes.
* Date input formats::                 Specifying date strings.
* Opening the software toolbox::       The software tools philosophy.
* GNU Free Documentation License::     The license for this documentation.
* Index::                              General index.

@detailmenu
 --- The Detailed Node Listing ---

Common Options

* Backup options::              Backup options
* Block size::                  Block size
* Target directory::            Target directory
* Trailing slashes::            Trailing slashes
* Standards conformance::       Standards conformance

Output of entire files

* cat invocation::              Concatenate and write files.
* tac invocation::              Concatenate and write files in reverse.
* nl invocation::               Number lines and write files.
* od invocation::               Write files in octal or other formats.

Formatting file contents

* fmt invocation::              Reformat paragraph text.
* pr invocation::               Paginate or columnate files for printing.
* fold invocation::             Wrap input lines to fit in specified width.

Output of parts of files

* head invocation::             Output the first part of files.
* tail invocation::             Output the last part of files.
* split invocation::            Split a file into fixed-size pieces.
* csplit invocation::           Split a file into context-determined pieces.

Summarizing files

* wc invocation::               Print byte, word, and line counts.
* sum invocation::              Print checksum and block counts.
* cksum invocation::            Print CRC checksum and byte counts.
* md5sum invocation::           Print or check message-digests.

Operating on sorted files

* sort invocation::             Sort text files.
* uniq invocation::             Uniquify files.
* comm invocation::             Compare two sorted files line by line.
* ptx invocation::              Produce a permuted index of file contents.
* tsort invocation::            Topological sort.

@command{ptx}: Produce permuted indexes

* General options in ptx::      Options which affect general program behavior.
* Charset selection in ptx::    Underlying character set considerations.
* Input processing in ptx::     Input fields, contexts, and keyword selection.
* Output formatting in ptx::    Types of output format, and sizing the fields.
* Compatibility in ptx::        The GNU extensions to @command{ptx}

Operating on fields within a line

* cut invocation::              Print selected parts of lines.
* paste invocation::            Merge lines of files.
* join invocation::             Join lines on a common field.

Operating on characters

* tr invocation::               Translate, squeeze, and/or delete characters.
* expand invocation::           Convert tabs to spaces.
* unexpand invocation::         Convert spaces to tabs.

@command{tr}: Translate, squeeze, and/or delete characters

* Character sets::              Specifying sets of characters.
* Translating::                 Changing one characters to another.
* Squeezing::                   Squeezing repeats and deleting.
* Warnings in tr::              Warning messages.

Directory listing

* ls invocation::               List directory contents
* dir invocation::              Briefly list directory contents
* vdir invocation::             Verbosely list directory contents
* dircolors invocation::        Color setup for @command{ls}

@command{ls}:  List directory contents

* Which files are listed::      Which files are listed
* What information is listed::  What information is listed
* Sorting the output::          Sorting the output
* More details about version sort::  More details about version sort
* General output formatting::   General output formatting
* Formatting the file names::   Formatting the file names

Basic operations

* cp invocation::               Copy files and directories
* dd invocation::               Convert and copy a file
* install invocation::          Copy files and set attributes
* mv invocation::               Move (rename) files
* rm invocation::               Remove files or directories
* shred invocation::            Remove files more securely

Special file types

* link invocation::             Make a hard link via the link syscall
* ln invocation::               Make links between files
* mkdir invocation::            Make directories
* mkfifo invocation::           Make FIFOs (named pipes)
* mknod invocation::            Make block or character special files
* rmdir invocation::            Remove empty directories
* unlink invocation::           Remove files via unlink syscall

Changing file attributes

* chown invocation::            Change file owner and group
* chgrp invocation::            Change group ownership
* chmod invocation::            Change access permissions
* touch invocation::            Change file timestamps

Disk usage

* df invocation::               Report filesystem disk space usage
* du invocation::               Estimate file space usage
* stat invocation::             Report file or filesystem status
* sync invocation::             Synchronize data on disk with memory

Printing text

* echo invocation::             Print a line of text
* printf invocation::           Format and print data
* yes invocation::              Print a string until interrupted

Conditions

* false invocation::              Do nothing, unsuccessfully
* true invocation::               Do nothing, successfully
* test invocation::               Check file types and compare values
* expr invocation::               Evaluate expressions

@command{test}: Check file types and compare values

* File type tests::               File type tests
* Access permission tests::       Access permission tests
* File characteristic tests::     File characteristic tests
* String tests::                  String tests
* Numeric tests::                 Numeric tests

@command{expr}: Evaluate expression

* String expressions::         + : match substr index length
* Numeric expressions::        + - * / %
* Relations for expr::         | & < <= = == != >= >
* Examples of expr::           Examples of using @command{expr}

Redirection

* tee invocation::               Redirect output to multiple files

File name manipulation

* basename invocation::          Strip directory and suffix from a file name
* dirname invocation::           Strip non-directory suffix from a file name
* pathchk invocation::           Check file name portability

Working context

* pwd invocation::               Print working directory
* stty invocation::              Print or change terminal characteristics
* printenv invocation::          Print all or some environment variables
* tty invocation::               Print file name of terminal on standard input