/* btoa: version 4.0 * stream filter to change 8 bit bytes into printable ascii * computes the number of bytes, and three kinds of simple checksums * incoming bytes are collected into 32-bit words, then printed in base 85 * exp(85,5) > exp(2,32) * the ASCII characters used are between '!' and 'u' * 'z' encodes 32-bit zero; 'x' is used to mark the end of encoded data. * * Paul Rutter Joe Orost * * 7/29/90: added input and output file handling so to run on VMS, DOS, etc --kang sun (sun@robios.eng.yale.edu) */ [ usage: A binary file, let is call it `bin_file', can be convert it to a ascii file `asc_file' by btoa < bin_file > asc_file This ascii file can be transmitted via email. The ascii file can be converted back to original binary file by atob < asc_file > bin_file xiaofei for ftp-admin@ifcss.org ]