Bug#669714: gawk: weird printf behaviour under locale different than C

[Santiago Vila]

Package: gawk
Version: 1:4.0.1+dfsg-1

I had this little script to generate a white pnm file:

#!/usr/bin/gawk -f
BEGIN {
  print "P5"
  print width " " height
  print "255"
  for (i=0;i<width*height;i++) {
    printf("%c",255)
  }
}

which I used in this way:

./mk-white-pgm -vwidth=100 -vheight=100 > white.pnm

but today I found (see attach) that it's not white anymore but grey (!).

The problem reproduces using `LANG=es_ES.UTF8'. Is it really correct
that printf and %c stop working to support UTF locales?

Thanks.

<<attachment: white.pnm>>