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getspnam(3C)		 Standard C Library Functions		  getspnam(3C)

NAME
       getspnam,  getspnam_r,  getspent, getspent_r, setspent, endspent, fget-
       spent, fgetspent_r - get	password entry

SYNOPSIS
       #include	<shadow.h>

       struct spwd *getspnam(const char	*name);

       struct spwd *getspnam_r(const char *name,  struct  spwd	*result,  char
       *buffer,	int buflen);

       struct spwd *getspent(void);

       struct spwd *getspent_r(struct spwd *result, char *buffer, int buflen);

       void setspent(void);

       void endspent(void);

       struct spwd *fgetspent(FILE *fp);

       struct  spwd  *fgetspent_r(FILE *fp, struct spwd	*result, char *buffer,
       int buflen);

DESCRIPTION
       These functions are used	to obtain shadow password entries.   An	 entry
       may  come from any of the sources for shadow specified in the /etc/nss-
       witch.conf file (see nsswitch.conf(4)).

       The getspnam() function searches	for a shadow password entry  with  the
       login name specified by the character string argument name.

       The   setspent(), getspent(), and endspent() functions are used to enu-
       merate shadow password entries from the database.

       The setspent() function sets (or	resets)	the enumeration	to the	begin-
       ning  of	 the  set of shadow password entries.  This function should be
       called before the first call to getspent(). Calls to  getspnam()	 leave
       the enumeration position	in an indeterminate state.

       Successive  calls  to  getspent()  return  either successive entries or
       NULL, indicating	the end	of the enumeration.

       The endspent() function may be called to	indicate that the  caller  ex-
       pects to	do no further shadow password retrieval	operations; the	system
       may then	 close the shadow password file, deallocate resources  it  was
       using, and so forth.  It	is still allowed, but possibly less efficient,
       for the process to call more shadow password  functions	after  calling
       endspent().

       The  fgetspent()	 function,  unlike the other functions above, does not
       use nsswitch.conf; it reads and parses the next line  from  the	stream
       fp,  which  is  assumed	to  have  the  format  of the shadow file (see
       shadow(4)).

   Reentrant Interfaces
       The  getspnam(),	getspent(), and	fgetspent() functions use  thread-spe-
       cific  data  storage  that is reused in each call to one	of these func-
       tions by	the same thread, making	them safe to use but  not  recommended
       for multithreaded applications.

       The   getspnam_r(),  getspent_r(),  and fgetspent_r() functions provide
       reentrant interfaces for	these operations.

       Each reentrant interface	performs the same operation as	its  non-reen-
       trant counterpart, named	by removing the	 _r suffix.  The reentrant in-
       terfaces, however, use buffers supplied by the caller to	store returned
       results,	 and   are  safe  for  use  in both single-threaded and	multi-
       threaded	applications.

       Each reentrant interface	takes the same argument	as  its	 non-reentrant
       counterpart, as well as the following additional	arguments.  The	result
       argument	must be	a pointer to a struct spwd structure allocated by  the
       caller.	 On  successful	 completion,  the  function returns the	shadow
       password	entry in this  structure.  The	 buffer	 argument  must	 be  a
       pointer	to  a  buffer  supplied	by the caller.	This buffer is used as
       storage space for the shadow password data.  All	of the pointers	within
       the returned struct spwd	result point to	data stored within this	buffer
       (see RETURN VALUES). The	buffer must be large enough to hold all	of the
       data  associated	 with  the  shadow password entry. The buflen argument
       should give the size in bytes of	the buffer indicated by	buffer.

       For enumeration in multithreaded	applications, the position within  the
       enumeration  is a process-wide property shared by all threads. The set-
       spent() function	may be used in a multithreaded application but	resets
       the  enumeration	 position for all threads.  If multiple	threads	inter-
       leave calls to getspent_r(), the	threads	will enumerate	disjoint  sub-
       sets of the shadow password database.

       Like its	non-reentrant counterpart, getspnam_r()	leaves the enumeration
       position	in an indeterminate state.

RETURN VALUES
       Password	entries	are represented	by the struct spwd  structure  defined
       in <shadow.h>:

       struct spwd{
	   char		   *sp_namp;	 /* login name */
	   char		   *sp_pwdp;	 /* encrypted passwd */
	   long		   sp_lstchg;	 /* date of last change	*/
	   long		   sp_min;	 /* min	days to	passwd change */
	   long		   sp_max;	 /* max	days to	passwd change*/
	   long		   sp_warn;	 /* warning period */
	   long		   sp_inact;	 /* max	days inactive */
	   long		   sp_expire;	 /* account expiry date	*/
	   unsigned long   sp_flag;	 /* not	used */
       };

       See shadow(4) for more information on the interpretation	of this	data.

       The   getspnam()and  getspnam_r()  functions each return	a pointer to a
       struct spwd if they successfully	locate the requested entry;  otherwise
       they return NULL.

       The   getspent(),  getspent_r(),	fgetspent(), and fgetspent() functions
       each return a pointer to	a struct spwd if they  successfully  enumerate
       an entry; otherwise they	return NULL, indicating	the end	of the enumer-
       ation.

       The  getspnam(),	getspent(), and	fgetspent() functions use  thread-spe-
       cific data storage, so returned data must be copied before a subsequent
       call to any of these functions if the data is to	be saved.

       When the	pointer	returned by the	reentrant functions getspnam_r(), get-
       spent_r(), and fgetspent_r() is non-null, it is always equal to the re-
       sult pointer that was supplied by the caller.

ERRORS
       The reentrant functions	getspnam_r(), getspent_r(), and	 fgetspent_r()
       will  return  NULL  and set errno to ERANGE if the length of the	buffer
       supplied	by caller is not large enough to store the  result.   See  in-
       tro(2)  for  the	 proper	 usage	and  interpretation of errno in	multi-
       threaded	applications.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |See "Reentrant  Interfaces"  |
       |			     |in DESCRIPTION.		   |
       +-----------------------------+-----------------------------+

SEE ALSO
       nispasswd(1),  passwd(1),  yppasswd(1), intro(3), getlogin(3C),	getpw-
       nam(3C),	nsswitch.conf(4), passwd(4), shadow(4),	attributes(5)

WARNINGS
       The reentrant interfaces	getspnam_r(), getspent_r(), and	 fgetspent_r()
       are included in this release on an uncommitted basis only, and are sub-
       ject to change or removal in future minor releases.

NOTES
       When compiling multithreaded applications, see intro(3),	Notes On  Mul-
       tithreaded  Applications,  for  information about the use of the	_REEN-
       TRANT flag.

       Use of the enumeration interfaces getspent() and	 getspent_r()  is  not
       recommended;  enumeration  is  supported	 for the shadow	file, NIS, and
       NIS+, but in general is not efficient and may not be supported for  all
       database	 sources.   The	semantics of enumeration are discussed further
       in nsswitch.conf(4).

       Access to shadow	password information may be restricted in a manner de-
       pending	on  the	database source	being used.  Access to the /etc/shadow
       file is generally restricted to processes running  with	the  effective
       uid  of	the  file  owner of the	{PRIV_FILE_DAC_READ} privilege.	 Other
       database	sources	may impose stronger or less stringent restrictions.

       When NIS	is used	as the	database  source,   the	 information  for  the
       shadow  password	 entries  is  obtained from the	``passwd.byname'' map.
       This map	stores only the	information for	the sp_namp and	sp_pwdp	fields
       of  the	struct	spwd structure.	 Shadow	password entries obtained from
       NIS will	contain	the value -1 in	the remainder of the fields.

       When NIS+ is used as the	database source, and the caller	lacks the per-
       mission	needed	to  retrieve  the  encrypted  password	from  the NIS+
       ``passwd.org_dir'' table, the NIS+ service returns the string  ``*NP*''
       instead	of  the	 actual	 encrypted password string.  The functions de-
       scribed on this page will then return the string	``*NP*'' to the	caller
       as  the	value  of  the	member sp_pwdp in the returned shadow password
       structure.

SunOS 5.10			  18 May 2004			  getspnam(3C)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO | WARNINGS | NOTES

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