how to append $var zeros to a string 3

[entrylevel]

Hi all,

is there a simple way in /bin/sh to append certain amount zeros at the begining of a string or at the end of a string.

say I want to add $var=5 zeros at the begining of the string "teststring", make it like "00000teststring"

and append $var=3 zeros at the end of the string "teststring", make it as "teststring000"

thanks and regards!

 

[futurelet]

[tt]
awk -v n=$var '
BEGIN{for(;i<n;i++)printf "0"
print "teststring"}'
[/tt]

 

[PHV]

beg=5;end=3;test=teststring
test=`printf "%0"$beg"d" 0`$test`printf "%0"$end"d" 0`
echo $test

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ222-2244

 

[entrylevel]

Hi thanks! that helps, by the way, is there a function to identify the length of the string, say...

the length of the string "teststring" is 10 (characters)? Thanks.

Regards!

 

[PHV]

expr length "$test"

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ222-2244

 

[entrylevel]

Hi,

How come I tried it on Linux/AIX/HP-UX with

expr length "string"

with no problem, but for solaris ... it says

# expr length "string"
expr: syntax error

# expr 8 + 6
14

thanks and regards!

 

[columb]

From man expr

  /usr/bin/expr
     Example 2: Return the number of bytes in $VAR:
 
     example$ expr "$VAR" : '.*'

Columb Healy

 

[columb]

given that you want to prepend zeros to a string and know how long a string is it looks like what you realy want to do is pad numeric variables with leading zeros to get a fixed length. If this is the case then, on Solaris ksh at least, try

printf "%10.10d" $myvar

Columb Healy

 

[entrylevel]

hi Columb,

thanks, yes that's what I wanted to do, can you explain a little what is %10 stand for? i tried with

printf "%8.10d" $myvar

got the same output with "%10.10d", want to learn the diff.

Regards!

 

[PHV]

And this ?
printf "%08d" $myvar

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ222-2244

 

[entrylevel]

hi PH,

yeah, that works too. what is that %0 ? thanks.


Regards!

 

[PHV]

man printf

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ222-2244

 

[columb]

A full explanation is given in

man format 5

The digit before the . is field width. For the %d format this is left padded with 0's as required. The digit after the . is precision and mainly relates to the %f or %g formats. I gave you both because I couldn't remember off the top of my head which was which. PHV's shorter simpler constuct will do just as well.

Columb Healy

 

[entrylevel]

thanks guys for pointing out.

Regards!