-w Mount the file system read-write. The options specific to NFS filesystems are described in the mount_nfs(8) manual page.
bogon:OperatingSystems Forever-Always$ sudo /sbin/mount_cd9660 -w /dev/disk2 /Volumes/redhat/
/sbin/mount_cd9660: illegal option — w
usage: mount_cd9660 [-egjr] [-o options] [-s startsector] special node
Who can tell me why?
The man page that you are showing is showing information about NFS. This is probably from the mount_nfs man page, or perhaps the mount man page.
This man page for iso9660 does not show such an option.
Understand that the “mount” command may simply pass information to a more specific executable that supports a filesystem, like mount_cd9660. If the specific filesystem driver doesn’t provide some functionality, like writability, then the “mount” command probably won’t support it either.
The typical approach to get an updated ISO 9660 file is to simply get all of the desired data in one location, and then make a brand new ISO 9660 file, entirely replacing the older one.
In theory, ISO 9660 data is information that gets stored on a disc/disk, and information can be written, so an ISO 9660 could be written to (in theory).
In practice, operating systems do not typically support real-time updating of ISO 9660 files. The file structure to ISO 9660 is designed in a way that makes real-time updating a challenge. UDF (more commonly found on DVDs, and usable on CDs with many operating systems) drivers will more commonly support a UDF feature called “packet writing”, which allows smaller/easier updates. So if you need a CD, and you don’t care about the format, you may wish to check out UDF as a possible option that might be relatively easy to implement. However, UDF is different than ISO9660, so if you’re still wanting ISO9660-compatibility, know that using UDF does not accomplish that goal.