serenity/Base/usr/share/man/man2/mount.md

Name

mount - mount a filesystem

Synopsis

#include <unistd.h>

int mount(const char* source, const char* target, const char* fs_type, int flags);

Description

mount() mounts a filesystem stored at source by overlaying its contents over target.

fs_type must be one of the following supported filesystems:

• Ext2FS (or ext2): The ext2 filesystem.
• ProcFS (or proc): The process pseudo-filesystem (normally mounted at /proc).
• DevPtsFS (or devpts): The pseudoterminal pseudo-filesystem (normally mounted at /dev/pts).
• TmpFS (or tmp): A non-persistent filesystem that stores all its data in RAM. An instance of this filesystem is normally mounted at /tmp.

For Ext2FS, source must be a path to a block device storing the filesystem contents. All the other filesystems ignore the source argument (by convention, it should have the same value as fs_type).

The following flags are supported:

• MS_NODEV: Disallow opening any devices from this file system.
• MS_NOEXEC: Disallow executing any executables from this file system.
• MS_NOSUID: Ignore set-user-id bits on executables from this file system.
• MS_BIND: Perform a bind-mount (see below).

These flags can be used as a security measure to limit the possible abuses of the newly mounted file system.

Bind mounts

If MS_BIND is specified in flags, fs_type is ignored and a bind mount is performed instead. In this case source is treated as a path to a file or directory whose contents are overlayed over target. This can be used as an alternative to symlinks or hardlinks.

Errors

• EPERM: The current process does not have superuser privileges.
• ENODEV: The fs_type is unrecognized, or the device is not found, or the device doesn't contain a valid filesystem image.

All of the usual path resolution errors may also occur.

See also

• mount(8)