Expr command

(Difference between revisions)

Revision as of 07:17, 13 February 2009

expr is the expression command in bourne type shells. On the WRT, expr is handled by busybox.

expr takes expressions. The most common expressions deal with simple arithmetic operations:

~ # expr 5   6
11

~ # expr 39 / 4
9

Loop counter example:

#!/bin/sh

# while lc < 10 do

lc=1
while [ $lc -lt 10 ] ;  do 
   lc=`expr $lc + 1`
   echo LoopCount: $lc
done

Try expr --help for more details.

Revision as of 19:00, 9 January 2009 (edit) Alvin (Talk \| contribs) m ← Previous diff		Revision as of 07:17, 13 February 2009 (edit) (undo) Alvin (Talk \| contribs) m Next diff →
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-	You are here: '''[[Main_Page\|DD-WRT wiki mainpage]] / [[Telnet/SSH_and_the_Command_Line\|SSH/Telnet & The CLI]] / expr '''	+	You are here: '''[[Main_Page\|DD-WRT wiki mainpage]] / [[Index:Scripting\|Scripting]] / [[Telnet/SSH_and_the_Command_Line\|SSH/Telnet & The CLI]] / expr '''

	'''expr''' is the expression command in bourne type shells. On the WRT, expr is handled by busybox.		'''expr''' is the expression command in bourne type shells. On the WRT, expr is handled by busybox.