Workfile

During a sort or merge operation, mfsort uses a temporary workfile. This workfile is paged to disk in the current directory or, if it is set, in the directory specified by the TMP or TEMP environment variable. If not set, the current working directory is used.

Mfsort copies all the records from each of the input files to the temporary workfile, truncated or padded as appropriate. The workfile is then sorted or merged according to its key description. After being sorted or merged in the workfile, the records are copied to each of the output files and truncated or padded as appropriate.

During this operation:

• If you do not need any of the records to be truncated, you must ensure that the record length of the workfile is sufficient for the longest record to be sorted
• If your input files are of variable length and the sort workfile is not, all concept of variable-length is lost
• If your input file is fixed length and the workfile is variable length, the record length of the record in the workfile is either the fixed length of the input file or the maximum record length of the workfile, whichever is the smaller