When printf is running builtin in a sh, global vars aren't reset to
0 between invocations. This affects "rval" which remembers state
from a previous %b \c and thereafter always exits after the first
format conversion, until we get a conversion that generates an
error (which resets the flag almost by accident)
printf %b abc\\c
abc (no \n)
printf %s%s hello world
hello (no \n, of course, no world ...)
printf %s%s hello world
hello
printf %s%s hello world
hello
printf %d hello
printf: hello: expected numeric value
0 (no \n)
printf %s%s hello world
helloworld (no \n, and we are back!)
This affects both /bin/sh and /bin/csh (and has for a very long time).
XXX pullup -8
f910883c96