@var{regexp} and @var{replace} are described in detail in
@ref{The "s" Command, The "s" Command, The `s' Command, sed, GNU sed}.
-The supported @var{flags} are:
+Supported @var{flags} are:
@table @samp
@item g
@var{regexp} is an @dfn{extended regular expression} (@pxref{Extended
regexps, Extended regular expressions, Extended regular expressions,
sed, GNU sed}.
+
+@item @var{number}
+Only replace the @var{number}th match of the @var{regexp}.
+
+Note: the @var{posix} standard does not specify what should happen
+when you mix the @samp{g} and @var{number} modifiers. @GNUTAR{}
+follows the GNU @command{sed} implementation in this regard, so
+the the interaction is defined to be: ignore matches before the
+@var{number}th, and then match and replace all matches from the
+@var{number}th on.
+
@end table
Any delimiter can be used in lieue of @samp{/}, the only requirement being