binsort

Binsort is a tool to sort files of fixed-length binary records.

Features:

• Can compare only a slice of records when sorting (i.e. it is possible to sort records by comparing only bytes 8-16 of each record)
• Uses external sorting to be able to sort files larger than main memory
• Treats records as abstract arrays of bytes. If the data contains integers, sorting gives expected results if they are encoded with their most significant byte first (i.e. in big endian order)

Install

go get github.com/arnaud-lb/binsort

This should leave a binsort binary in $GOPATH/bin/

Usage

binsort --size|-s record_size [OPTIONS] infile outfile

Options

-s, --size=BYTES
    Record size in bytes (mandatory).

-o, --offset=BYTES
    Ignore the first bytes in record for sorting. Defaults to 0.

-l, --length=BYTES
    Use only length bytes for sorting. Defaults to size-offset.

-b, --block-size=RECORDS
    Sort this number of records at once. This determines the
    maximum number of records kept in memory at any time. Defaults
    to the greatest of 1MB or 4 records. More is faster.

-T, --temporary-directory=DIR
    Use DIR as temporary directory instead of the system
    default. binsort may need to create files as big as the
    input file.

Examples

Sort a file composed of 32-bytes records, by comparing only 8 bytes, starting at byte 16 in each record:

binsort --size 32 --offset 16 --length 8 ./input ./output