minssl
Software
www.skarnet.org

The hexawrite program

hexawrite reads a certain number of ASCII hexadecimal characters and writes the represented binary bytes.

Interface

     hexawrite [ -n numchars ]

• hexawrite reads 2*numchars bytes on stdin, followed by a newline. If some bytes are not in the 0-9, a-f or A-F range, hexawrite complains ans exits 100.
• It converts every sequence of 2 characters into the corresponding binary byte, and writes those numchar bytes to stdout. By default, numchars is 28.

Notes

hexawrite can be used to convert human-readable keys to nistp224 binary form.

hexawrite's dual is hexaread.