NAME 

rhmask - generates and recovers file masks

SYNOPSIS 

rhmask <infile> <maskfile> rhmask -d <infile> <outfile> <maskfile>

DESCRIPTION 

The rhmask utility creates mask files from original and updated files. The mask files, which may be the latest new versions of software, can then be freely distributed on public Internet servers. The mask files are only useful for people who already have a copy of the original package. The rhmask utility uses a simple XOR scheme for creating the file mask and uses file size and md5 sums to ensure the integrity of the result.

There are three files involved in this process. The first is the file which both parties must have, which is referred to as the infile. The file which the user would like to end up with is the outfile and the mask generated between the two is the maskfile.

OPTIONS 

There are two ways of running rhmask. Most users will only use it to recover the original file by giving the path to the infile as the first argument and the maskfile as the second argument. The outfile will be generated in the current directory and checked for correctness.

To generate the masks, the other form of rhmask must be used instead. The first parameter, -d indicates that you are generating a delta. The next parameter is the infile which is followed by the outfile. The final parameter is the file name to store the maskfile in. If the operation is successful, no output is produced.

SEE ALSO 

md5sum(1)

AUTHOR 

Erik Troan <