printf formats

The format-string can be a variable or a string, but it mostly consists of normal characters which are simply copied to stdout, escape sequences (which are converted and copied to stdout), and format specifications, each of which causes printing of the next successive argument.

In addition to the standard printf(3) formats (see_both: <http://www.daemon-systems.org/man/printf.1.html> <http://www.gnu.org/software/bash/manual/bashref.html>), %b means to expand escape sequences inside the corresponding argument, and %q means to quote the argument in such a way that it can be reused as shell input (for example \ becomes \\).