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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
              anchored pattern match of REGEXP in STRING
       match STRING REGEXP
              same as STRING : REGEXP
       substr STRING POS LENGTH
              substring of STRING, POS counted from 1
       index STRING CHARS
              index in STRING where any CHARS is found, or 0
       length STRING
              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 lexicographi-
       cal.  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 syntactically 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  (C) 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 permitted 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 2020                         EXPR(1)