grp.h File Reference

Defines the structures and functions for managing groups. More...

Go to the source code of this file.

Classes
struct	group
	Contains user group informations. More...

Macros
#define	MAX_MEMBERS_PER_GROUP   64
	Maximum number of users per group.

Typedefs
typedef struct group	group_t
	Contains user group informations.

Functions
group_t *	getgrgid (gid_t gid)
	Provides access to the group database entry for uid. More...
group_t *	getgrnam (const char *name)
	Provides access to the group database entry for name. More...
int	getgrgid_r (gid_t gid, group_t *group, char *buf, size_t buflen, group_t **result)
	Provides the same information as getgrgid but it stores the results inside group, and the string information are store store inside buf. More...
int	getgrnam_r (const char *name, group_t *group, char *buf, size_t buflen, group_t **result)
	Provides the same information as getgrnam but it stores the results inside group, and the string information are store store inside buf. More...
group_t *	getgrent (void)
	Returns a pointer to a structure containing the broken-out fields of an entry in the group database. More...
void	endgrent (void)
	Rewinds the group database to allow repeated searches.
void	setgrent (void)
	May be called to close the group database when processing is complete.

Detailed Description

Defines the structures and functions for managing groups.

Copyright

(c) 2014-2024 This file is distributed under the MIT License. See LICENSE.md for details.

Function Documentation

getgrent()

group_t* getgrent

(

void

)

Returns a pointer to a structure containing the broken-out fields of an entry in the group database.

Returns

pointer to the group entry.

When first called returns a pointer to a group structure containing the first entry in the group database. Thereafter, it returns a pointer to a group structure containing the next group structure in the group database, so successive calls may be used to search the entire database.

getgrgid()

group_t* getgrgid

(

gid_t

gid

)

Provides access to the group database entry for uid.

Parameters

gid	The gid to search inside the database.

Returns

A pointer to the structure containing the database entry.

getgrgid_r()

int getgrgid_r	(	gid_t	gid,
		group_t *	group,
		char *	buf,
		size_t	buflen,
		group_t **	result
	)

Provides the same information as getgrgid but it stores the results inside group, and the string information are store store inside buf.

Parameters

gid	The uid to search inside the database.
group	The structure containing pointers to the entry fields.
buf	The buffer where the strings should be stored.
buflen	The lenght of the buffer.
result	A pointer to the result or NULL is stored here.

Returns

If the entry was found returns zero and set *result to group, if the entry was not found returns zero and set *result to NULL, on failure returns a number and sets and set *result to NULL.

getgrnam()

group_t* getgrnam

(

const char *

name

)

Provides access to the group database entry for name.

Parameters

name	The name to search inside the database.

Returns

A pointer to the structure containing the database entry.

getgrnam_r()

int getgrnam_r	(	const char *	name,
		group_t *	group,
		char *	buf,
		size_t	buflen,
		group_t **	result
	)

Provides the same information as getgrnam but it stores the results inside group, and the string information are store store inside buf.

Parameters

name	The name to search inside the database.
group	The structure containing pointers to the entry fields.
buf	The buffer where the strings should be stored.
buflen	The lenght of the buffer.
result	A pointer to the result or NULL is stored here.

Returns

If the entry was found returns zero and set *result to group, if the entry was not found returns zero and set *result to NULL, on failure returns a number and sets and set *result to NULL.