ref: ffb48be969338833a69e576e7d62353bbd831226
dir: /sys/man/1/qr/
.TH QR 1 .SH NAME qr \- generate QR code .SH SYNOPSIS .B qr [ .B -LMQHna ] [ .B -v .I version ] .SH DESCRIPTION .I Qr generates a QR code from the data it reads on standard input. The QR code is generated as an .IR image (6) on standard output. .PP The .B -LMQH options set the level of error correction. .B -L is the lowest and .B -H is the highest level. The default is .BR -M . .PP The QR standard defines different sizes labelled version 1 to version 40. By default the smallest possible is chosen automatically. The .B -v option forces the use of a particular version. .PP By default bytes are encoded directly with no translation. Coding efficiency can be increased by reducing the set of legitimate characters using the .B -an options. The .B -n option supports only numbers and the .B -a option supports letters, numbers, spaces and the symbols .LR $%*+-./: . Note that all letters are converted to upper case. Both options ignore any characters they do not recognize. .SH SOURCE .B /sys/src/cmd/qr.c .SH "SEE ALSO" International Standard ISO/IEC 18004. .SH BUGS The standard specifies the use of JIS-8 encoding in the default mode, however rumour has it that readers recognize UTF-8. .PP The more advanced coding features (Kanji mode, extended modes, switching modes midstream) are not supported.