/usr/gnu/man2/cat.1/expr.1.Z(/usr/gnu/man2/cat.1/expr.1.Z)

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.

AUTHOR

       Written by Mike Parker.

REPORTING BUGS

       Report bugs to <bug-coreutils@gnu.org>.

COPYRIGHT

       Copyright (C) 2005 Free Software Foundation, Inc.
       This is free software.  You may redistribute copies  of  it  under  the
       terms       of       the      GNU      General      Public      License
       <http://www.gnu.org/licenses/gpl.html>.  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 expr

       should give you access to the complete manual.

expr 5.93                        November 2005                         EXPR(1)