This chapter gives an overview of the SWAP procedure for truncating records.
SWAP allows you to truncate records to a maximum length. Records less than the maximum length are left unchanged. You specify the maximum record length using the /LENGTH qualifier. If you specify a length greater than the RMS maximum record length (EDT creates text files with a maximum length of 255 bytes) for the file, the lesser value will be used. When using the menu control record length through the Truncate Length item on the modify setup menu.
If you want to truncate all the records in a file (or group of files) but do not want to perform a substitution, use the following command:
$ SWAP/LENGTH=n/STATISTICS file_name.ext "" ""
The above command will truncate all records in file_spec.ext to n bytes. It will not perform any other substitution.
NOTE: Record truncation is done AFTER the record is searched for strings. Records are truncated within the /RANGE boundaries ONLY. It is strongly suggested that the /STATISTICS qualifier be used with the /LENGTH=n qualifier. This will provide statistics regarding the number of records truncated.