The file is actually packed by creating a new temporary file called isfix and copying the old file to the new file record by record.  This is done so that if the pack process is interrupted, the original file is left untouched.  Consequently, there must be sufficient disk space for at least two copies of the file in question.

Currently, the pack process uses only about 75% of each data page, leaving the remaining 25% available for expansion.  This may cause the size of a file to actually increase after being packed.

It is vital that ispack is run from within the directory which contains the files to be packed. It is a good practice to run ischk and make a back-up copy of a file before a pack is attempted.  Packing a damaged file will result in further damage and could destroy the file. ispack must not be executed on  If ispack is entered without any parameters, then on-line help appears for the utility.

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Topic ID: 720188