UNIX for Dummies Questions & Answers

 
if a=12345678 i need to check that "a" 
less than 8 char
greater than 8 char
equal to 8 char
contain only numeric.

 
OS:SUNOS
script:shell scripting

len=`echo "$a" | awk '{print length}'`
if [ $len -lt 8 ]
then
 echo "less than 8"
elif [ $len -gt 8 ]
then
 echo "greater than 8"
elif [ -z `echo "$a" | tr -d '[0-9]'` ]
then
 echo "8 digits"
else
 echo "8 characters"
fi