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:
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 "${#myVar}"
Sample outputs:
8
Another option is to use Perl or Python:
echo "What you seek is seeking you" | perl -nle ' print length '
Sample outputs:
28
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thank you
One previous suggestion was:
echo "${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 "${myVar}" : '.*'Finding length of the string
expr “abcd” : ‘.*’
o/p 4
Just add this to your .bashrc:
——- cut ——-
strlen() { str="$@" echo ${#str} }—— end cut ——
Then all you need is:
$ strlen This is some string19
$ strlen "a"1
;]
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
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.
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
I 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 $A % 2` -eq 0 ]
then
echo “Number is even”;
else
echo “Number is odd”;
fi
Another simple way is:
mystr="A random string by alhaizan" len=${#mystr} echo $lenMore options 😀
myVar="nixcraft" echo ${#myVar} echo ${myVar} | awk ' { print length } ' echo "${myVar}" | wc -c echo `expr length ${myVar}`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.
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
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
use length=`expr length $string` it will work
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”.
Thanks for the tips
It was very useful for my work
Greetings from Mexico
echo -n “hello world” | wc -c
Corey,
Nice awk / perl tips 🙂
Appreciate your post!
Few more examples:
% echo nixcraft | awk ' { print length } '8