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EXPR(1)                                             User Commands                                             EXPR(1)



NAME
       expr - evaluate expressions

SYNOPSIS
       expr EXPRESSION
       expr OPTION

DESCRIPTION
       --help display this help and exit

       --version
              output version information and exit

       Print  the value of EXPRESSION to standard output.  A blank line below separates increasing precedence groups.
       EXPRESSION may be:

       ARG1 | ARG2
              ARG1 if it is neither null nor 0, otherwise ARG2

       ARG1 & ARG2
              ARG1 if neither argument is null or 0, otherwise 0

       ARG1 < ARG2
              ARG1 is less than ARG2

       ARG1 <= ARG2
              ARG1 is less than or equal to ARG2

       ARG1 = ARG2
              ARG1 is equal to ARG2

       ARG1 != ARG2
              ARG1 is unequal to ARG2

       ARG1 >= ARG2
              ARG1 is greater than or equal to ARG2

       ARG1 > ARG2
              ARG1 is greater than ARG2

       ARG1 + ARG2
              arithmetic sum of ARG1 and ARG2

       ARG1 - ARG2
              arithmetic difference of ARG1 and ARG2

       ARG1 * ARG2
              arithmetic product of ARG1 and ARG2

       ARG1 / ARG2
              arithmetic quotient of ARG1 divided by ARG2

       ARG1 % ARG2
              arithmetic remainder of ARG1 divided by ARG2

       STRING : REGEXP

              length of STRING

       + TOKEN
              interpret TOKEN as a string, even if it is a

              keyword like 'match' or an operator like '/'

       ( EXPRESSION )
              value of EXPRESSION

       Beware that many operators need to be escaped or quoted for shells.  Comparisons are arithmetic if  both  ARGs
       are numbers, else lexicographical.  Pattern matches return the string matched between \( and \) or null; if \(
       and \) are not used, they return the number of characters matched or 0.

       Exit status is 0 if EXPRESSION is neither null nor 0, 1 if EXPRESSION is null or 0, 2 if EXPRESSION is syntac‐
       tically invalid, and 3 if an error occurred.

       GNU   coreutils   online  help:  <http://www.gnu.org/software/coreutils/>  Report  expr  translation  bugs  to
       <http://translationproject.org/team/>

AUTHOR
       Written by Mike Parker, James Youngman, and Paul Eggert.

COPYRIGHT
       Copyright  ©  2013  Free  Software  Foundation,  Inc.   License  GPLv3+:  GNU   GPL   version   3   or   later
       <http://gnu.org/licenses/gpl.html>.
       This  is  free software: you are free to change and redistribute it.  There is NO WARRANTY, to the extent per‐
       mitted by law.

SEE ALSO
       The full documentation for expr is maintained as a Texinfo manual.  If the info and expr programs are properly
       installed at your site, the command

              info coreutils 'expr invocation'

       should give you access to the complete manual.



GNU coreutils 8.22                                  November 2016                                             EXPR(1)