Bkshuf

bkshuf is a variant of shuf that clumps output so each line's neighbors in the input line list tend to remain neighbors in the output line list.

Stats

• Project No.: BK-2020-03

Version history

• v0.1.2: 2023-03-04: GitLab

Objective

The author desires to create a shuf-like utility named bkshuf to mix line lists in order to produce output line lists with the following somewhat conflicting properties:

Pre-image resistance (PIR)

An output line's position should not contain information about its input line position.

Relative order preservation (ROP)

Two neighboring lines in the input stream should have a high probability of remaining neighbors in the output stream.

The objective is to improve the value of a short random scan of a small fraction of a potentially large input list; output that demonstrates ROP as well as some degree of PIR may achieve this objective. In contrast, the shuf utility provides PIR but no ROP: a line's neighbor in the output of shuf is equally likely to be any other random line from the input.

See also

• Wikipedia:shuf
• BK-2020-03: personal executables

External links

• bk4, reboil.com
• 2023-02-14 write-up