how to find the actual length of the string

[prakash(jp)]

[dbzTHEdinosauer]

string concept is not the same on mainframe cobol as it is on the toys or with c.

data is contained within fixed length fields in working-storage.
data is contained within variable length columns in db2
data is contained within variable length records in files

so you need to understand the mainframe concept of data,
suggest you read the Cobol Programmers Guide to understand all mainframe concepts.

without knowing the delimiter, you can only determine:

• the length of the variable containing the data
• the length of data up to but not including trailing spaces

by the way, just using the topic as you discussion is poor manners.