Alright, sorry for the noise. Is this minimal sync plus stdout mention fine?
Index: rdsetroot.8 =================================================================== RCS file: /cvs/src/usr.sbin/rdsetroot/rdsetroot.8,v retrieving revision 1.2 diff -u -p -r1.2 rdsetroot.8 --- rdsetroot.8 5 Apr 2019 21:44:32 -0000 1.2 +++ rdsetroot.8 20 Jan 2023 16:58:56 -0000 @@ -45,6 +45,11 @@ Debug. Rather than inserting, extract the .Ar disk.fs image. +If +.Ar disk.fs +is not speficied, +.Nm +writes to standard output. The disk can be made accessible using .Xr vnconfig 8 , filesystems can be manipulated, and finally re-inserted into the RAMDISK kernel. Index: rdsetroot.c =================================================================== RCS file: /cvs/src/usr.sbin/rdsetroot/rdsetroot.c,v retrieving revision 1.3 diff -u -p -r1.3 rdsetroot.c --- rdsetroot.c 24 Oct 2021 21:24:19 -0000 1.3 +++ rdsetroot.c 20 Jan 2023 16:58:58 -0000 @@ -294,6 +294,6 @@ usage(void) { extern char *__progname; - fprintf(stderr, "usage: %s [-dx] bsd [fs]\n", __progname); + fprintf(stderr, "usage: %s [-dx] kernel [disk.fs]\n", __progname); exit(1); }