Determining length of string


 
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# 1  
Old 08-05-2015
Determining length of string

I have this script which is very easy:

Code:
file=`echo 01114`
echo $file
01114

then I ran this
Code:
if [ $file -ge 7 ]; then echo "yes";fi

it returned yes even though there are only 5 digits there

So then I tried
Code:
file=`echo abcd`
echo $file
abcd

Code:
if [[ $file -ge 1 ]]; then echo "yes";fi

Code:
if [[ $file -gt 1 ]]; then echo "yes";fi

It did not return anything. How can I check with bash the length of a string of characters? I must be missing something
# 2  
Old 08-05-2015
Try:

Code:
[ "${#file}" -gt 7 ] && echo yes

Note the hash char between the bracket and variable name.

hth
This User Gave Thanks to sea For This Post:
# 3  
Old 08-06-2015
By way of explanation, your code is trying to compare the numeric value of the variable, not the length. The code from sea uses an in-built function to generate the length as a value to compare against, although I would prefer it without the double-quotes. It might work depending on your OS. Some may be picky and complain that you are comparing a string with a numerical operator (the -gt)


I hope that this helps,
Robin
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