Linux proc dir entry

low_ino The inode number of this directory entry. For proc_register this number should be unique within the /proc filesystem, values are defined in . For proc_register_dynamic the inode number is dynamically assigned. namelen The length of the name, excluding the trailing null. name The name of this node. mode The node’s type and permissions. Drawn from . nlink Number of links to the node. Initialise to 2 if mode includes S_IFDIR, 1 otherwise. uid The uid that owns the node, normally 0. gid The gid that owns the node. normally 0. size Sets the size of the node, the value will appear as the inode size in listings and be returned by stat . Unless you really need a size, set this to zero. ops Defines the set of inode operations to perform for your /proc node. For a directory node, use &proc_dir_inode_operations unless you have special requirements. For a leaf node, set to NULL unless you have special requirements. get_info If defined, this proc is called when the node is read. Should be NULL for directory nodes. NOTE: If you need to return large amounts of data, the proc must return the data in chunks and reposition itself on the next call, using the offset variable. See ip_masq_procinfo for example code with large output. fill_inode Dynamically fill in the inode characteristics during directory operations. Not normally required and set to NULL. See proc_pid_fill_inode for example code. next, parent, subdir Maintained by /proc routines. Initial value is irrelevant, set to NULL. data An opaque pointer which can be used by proc handlers to pass local data around. Set to whatever you like when calling proc_register , normally NULL. This pointer is copied into the inode u.ip_generic field (by proc_get_inode) so it is available to any proc routines that are passed an inode.

proc_register adds the child as a node under the parent .

proc_register_dynamic dynamically assigns an inode number then adds the child as a node under the parent .

proc_unregister scans the inode list under the parent for the specified inode number and removes the matching entry.

RETURN VALUE

proc_register always returns 0.

proc_register_dynamic returns 0 for success or -EAGAIN if there are no free dynamic inode numbers.

proc_unregister returns 0 for success or -EINVAL if the node was not found.

SEE ALSO

AUTHOR

BUGS

The uniqueness of /proc inode numbers is assumed, not enforced. It is possible to add two nodes with the same inode number.

Источник

Linux proc dir entry

#include int proc_register(struct proc_dir_entry * parent , struct proc_dir_entry * child); int proc_unregister(struct proc_dir_entry * parent , int inode); int proc_register_dynamic(struct proc_dir_entry * parent , struct proc_dir_entry * child);

DESCRIPTION

The proc_register functions add file or directory entries to the /proc file system. They associate processing routines with each node of the /proc tree. The structure proc_dir_entry is defined as

struct proc_dir_entry  unsigned short low_ino; unsigned short namelen; const char *name; mode_t mode; nlink_t nlink; uid_t uid; gid_t gid; unsigned long size; struct inode_operations * ops; int (*get_info)(char *buffer, char **start, off_t offset, int length, int unused); void (*fill_inode)(struct inode *); struct proc_dir_entry *next, *parent, *subdir; void *data; >; 

struct proc_dir_entry  unsigned short low_ino; unsigned short namelen; const char *name; mode_t mode; nlink_t nlink; uid_t uid; gid_t gid; unsigned long size; struct inode_operations * ops; int (*get_info)(char *buffer, char **start, off_t offset, int length, int unused); void (*fill_inode)(struct inode *); struct proc_dir_entry *next, *parent, *subdir; void *data; >;