While writing a shell script you may want to find out the length of a string. While reading GNU expr command man page I found an interesting option as follows:
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expr length STRING
For example display the length of “nixcraft” word/string, enter:
expr length "nixcraft" |
OR set it as follows:
var="nixcraft" expr "${var}" : '.*' |
Sample outputs:
8
Finding length of string in bash
The syntax is as follows:
var="nixCraft" l=${#var} echo "Length of string \"${var}\" is ${l}." |
Sample outputs:
Length of string "nixCraft" is 8.
String length in ksh or older unix oses
You can use the wc command as follows:
## pass the -c option to wc to get the number of bytes in $domain variable ## domain='www.cyberciti.biz' echo -n "$domain" | wc -c |
Sample outputs:
17
expr and POSIX
Please note that the expr command is not concerned with POSIX (open system standards based on Unix). You can try old good KSH/SH/Bash command as follows which should work with any UNIX-likeo operating systems such as FreeBSD, OpenBSD, Solaris, IBM AIX, HP-UX and more:
myVar="nixcraft" echo "${#myVar}" |
Sample outputs:
8
Another option is to use Perl or Python:
echo "What you seek is seeking you" | perl -nle ' print length ' |
Sample outputs:
28
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Few more examples:
% echo nixcraft | awk ' { print length } '8
Corey,
Nice awk / perl tips 🙂
Appreciate your post!
echo -n “hello world” | wc -c
Thanks for the tips
It was very useful for my work
Greetings from Mexico
hi i tried this program but its not working in my computer lab.
kindly let me know what is wrong in the program
echo enter the string
read string
length = ‘expr length $string’
echo “length of the string is $length”
output should come as
eg:
enter the string:Harshi
length of the string is :6
but in the lab its coming as
enter the string :Harshi
length command cannot be read
please try to solve my problem
thank you
to hw,
the correct code is:
echo enter the string
read string
length=$(expr length “$string”)
echo “length of the string is $lengthâ€
You must redirect the output into the variable, otherwise it don’t read the value.
Nice job.
i dunno y it is not working .have u given the inverted commas and stuffs??
this code worked for me..
echo ” enter thestring”
read str
len=`expr length $str`
echo “Length is $len”.
use length=`expr length $string` it will work
I am trying to create a string that will allow me to set value a a particular position in the string.
I am running a validation an have many for loops with various variable lengths being returned.
I want the output to be formatted so that the status is lined up in the same postion.
for example i check a list of files to see if they exist and I want to display an OK or FAILED in the output. I want the output to look like something below.
/IDS
sorry I didnt finish what I wanted to explain.
I am trying to create a string that will allow me to set value a a particular position in the string.
I am running a validation an have many for loops with various variable lengths being returned.
I want the output to be formatted so that the status is lined up in the same postion.
for example i check a list of directories to see if they exist and I want to display an OK or FAILED in the output. I want the output to look like something below.
/IDS [ OK ]
/VALID [ OK ]
/DEVEL [FAILED]
/PROGRAMS [ OK ]
any help
Hey !
Thanks for the tip ! resolved my issue !
Expr lenght was working under linux but not under Solaris.
The command `expr length $var` is platform dependent.You can not run it in another platform rather than the Linux.But if you using the command `echo ${#var}`, you can run it in cross platform.
More options 😀
myVar="nixcraft" echo ${#myVar} echo ${myVar} | awk ' { print length } ' echo "${myVar}" | wc -c echo `expr length ${myVar}`Another simple way is:
mystr="A random string by alhaizan" len=${#mystr} echo $lenI want program code for “Accept number and check the number is even or odd, finds the length of the number, sum of the digits in the number” in Unix.
# to find Even or Odd
echo “Enter the A value”;
read A
if [ `expr $A % 2` -eq 0 ]
then
echo “Number is even”;
else
echo “Number is odd”;
fi
Hi All,
I am looking for a script to compare the dates of two files to find out which one is newer.
Taking the following files as reference:
-rwxr-xr-x 1 vishy vishy 10088 Apr 26 11:08 file1
-rwxrwxr-x 1 vishy vishy 3232 Feb 12 2009 file2
We can see that for file1 the date and time(month date hrs:mins) is displayed, but for file2 month date and year is displayed.
Can anyone please share a script to compare the dates of files of these kind?
Regards,
Vishy
what is the code for generating the number of char for A and B for unix and I want the input of the user to be prompted every time a input is done (e.g. loop)
So I would want te program to allow the user to repeatedly input a string of characters and produce the list of number of each character in the string and generate the percentage of each character in the string.
Any suggestions.
echo “enter 1se file name”
read f1
echo “enter 2nd fname”
read f2
if [ $f1 -nt -$f2 ]
then
echo ” $f1 is newer”
else
echo ” $f2 is newer”
fi
Just add this to your .bashrc:
——- cut ——-
strlen() { str="$@" echo ${#str} }—— end cut ——
Then all you need is:
$ strlen This is some string19
$ strlen "a"1
;]
One previous suggestion was:
echo "${myVar}" | wc -cHowever this includes the trailing character so the length is out by 1.
Using a generic expr command you can get the length on almost any platform or shell:
expr "${myVar}" : '.*'Finding length of the string
expr “abcd” : ‘.*’
o/p 4
thank you