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Full Discussion: Maths in shell scripts
Top Forums Shell Programming and Scripting Maths in shell scripts Post 302589243 by vchee on Wednesday 11th of January 2012 05:38:25 AM
Old 01-11-2012
Maths in shell scripts

Hi,

Need help on this. I need to increment a variable by 1 but retain as 2 characters.

I am using expr to do additions:
Code:
NEWSERIAL=`expr $SERIAL + 1`

$SERIAL can range from 01-99. After adding "1", I need the result to be 2 characters, eg: 02+1 = 03. By default expr will truncate the zero such that 02+1 will become "3" not "03"

Please help. Much appreciated.

Thanks.

Last edited by Franklin52; 01-11-2012 at 07:24 AM.. Reason: Please use code tags for code and data samples, thank you
 

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let(1)								   User Commands							    let(1)

NAME
let - shell built-in function to evaluate one or more arithmetic expressions SYNOPSIS
ksh let arg... ksh93 let [expr...] DESCRIPTION
ksh Each arg is a separate arithmetic expression to be evaluated. ksh93 let evaluates each expr in the current shell environment as an arithmetic expression using ANSI C syntax. Variables names are shell vari- ables and they are recursively evaluated as arithmetic expressions to get numerical values. let has been made obsolete by the ((...)) syn- tax of ksh93(1) which does not require quoting of the operators to pass them as command arguments. EXIT STATUS
ksh ksh returns the following exit values: 0 The value of the last expression is non-zero. 1 The value of the last expression is zero. ksh93 ksh93 returns the following exit values: 0 The last expr evaluates to a non-zero value. >0 The last expr evaluates to 0 or an error occurred. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
ksh(1), ksh93(1), set(1), typeset(1), attributes(5) SunOS 5.11 2 Nov 2007 let(1)
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