mmount

mmount [-a] [-D drive:path] [-F file] [-o option] [mountpoint] [drive:]

-a
    Attempts to "mount" all drives defined in the mtools configuration file automatically.

-D drive:path
    Defines a temporary DOS drive mapping. Associates a DOS drive letter (e.g., A:) with a Linux device file or directory (e.g., /dev/fd0). This mapping overrides any existing mapping for the duration of the command.

-F file
    Specifies an alternative mtools configuration file to use, overriding the default ~/.mtoolsrc or /etc/mtools.conf.

-o option
    Passes specific mtools configuration options (e.g., fat_access=rw), which can override settings from the configuration file.

mountpoint
    The directory where mmount should operate as if the DOS filesystem is "mounted". This often corresponds to a device defined in mtools.conf.

drive:
    The specific DOS drive letter (e.g., A:, C:) to be "mounted" or configured for mtools operations.

mmount is a utility from the mtools suite, designed to facilitate interaction with MS-DOS formatted filesystems from a Linux environment. Unlike the standard mount(8) command, mmount does not perform a true kernel-level mount operation. Instead, it configures the mtools environment, making it appear as if a DOS filesystem is mounted and accessible to other mtools utilities like mcopy or mdir.

Its primary purpose is to simplify access to legacy media such as floppy disks or disk images containing DOS filesystems. It allows users to define temporary drive mappings and specify configuration options, effectively setting up a working context for subsequent mtools operations without requiring root privileges for a full system mount. This makes it particularly useful for handling older DOS media or when a full kernel mount is unnecessary or undesirable.

mmount does not perform a true kernel-level filesystem mount. It is a utility from the mtools suite that configures the environment for other mtools commands to access DOS filesystems. Consequently, filesystems handled by mmount will not appear in the output of standard Linux commands like df or mount.

It is primarily designed for MS-DOS formatted media (such as floppy disks or older disk images) and may not fully support modern FAT32 features or other filesystems like NTFS or ext4. Access permissions and certain filesystem operations might behave differently compared to native Linux mounts. The mtools package must be installed on the system for mmount to be available and functional.

mmount heavily relies on the mtools configuration file (typically ~/.mtoolsrc in the user's home directory or /etc/mtools.conf system-wide). This file defines the permanent drive mappings (e.g., A: to /dev/fd0) and default access permissions. Without proper configuration in these files, mmount might not be able to locate or operate on the intended DOS devices. The command-line options like -D and -F can temporarily override or specify alternative configuration sources.

It is critical to understand that mmount creates an emulated mount environment for mtools utilities, rather than a true filesystem mount registered with the Linux kernel. This means that standard Linux commands like ls, cp, or cat cannot directly access files through the "mountpoint" established by mmount. Instead, you must use their mtools counterparts, such as mdir, mcopy, or mtype, respectively, to interact with the DOS filesystem.

The mtools suite, which includes mmount, emerged in the early days of Linux to provide robust and convenient tools for interacting with MS-DOS filesystems. During a time when DOS was prevalent and Linux kernel support for DOS filesystems was less mature or less user-friendly, mtools offered a crucial bridge. It allowed users to access and manipulate files on DOS-formatted floppy disks or hard drives without needing root privileges for every mount/unmount cycle, streamlining workflows for dual-boot systems or systems frequently handling DOS media. While its necessity has diminished with the decline of floppy drives and the maturation of kernel-level FAT support, mtools (and mmount) remains a valuable tool for specific niche applications, such as data recovery from legacy media or embedded systems interactions.

mount(8), umount(8), mtools(1), mcopy(1), mdir(1)