GETPROJENT(3PROJECT) Project Database Access Library Functions

NAME


getprojent, getprojbyname, getprojbyid, getdefaultproj, inproj,
getprojidbyname, setprojent, endprojent, fgetprojent - project database
entry operations

SYNOPSIS


cc [ flag... ] file... -lproject [ library... ]
#include <project.h>

struct project *getprojent(struct project *proj, void *buffer,
size_t bufsize);


struct project *getprojbyname(const char *name,
struct project *proj, void *buffer, size_t bufsize);


struct project *getprojbyid(projid_t projid,
struct project *proj, void *buffer, size_t bufsize);


struct project *getdefaultproj(const char *username,
struct project *proj, void *buffer, size_t bufsize);


int inproj(const char *username, const char *projname,
void *buffer, size_t bufsize);


projid_t getprojidbyname(const char *name);


void setprojent(void);


void endprojent(void);


struct project *fgetprojent(FILE *f, struct project *proj,
void *buffer, size_t bufsize);


DESCRIPTION


These functions are used to obtain entries describing user projects.
Entries can come from any of the sources for a project specified in the
/etc/nsswitch.conf file (see nsswitch.conf(5)).


The setprojent(), getprojent(), and endprojent() functions are used to
enumerate project entries from the database.


The setprojent() function effectively rewinds the project database to
allow repeated searches. It sets (or resets) the enumeration to the
beginning of the set of project entries. This function should be called
before the first call to getprojent().


The getprojent() function returns a pointer to a structure containing the
broken-out fields of an entry in the project database. When first called,
getprojent() returns a pointer to a project structure containing the
first project structure in the project database. Successive calls can be
used to read the entire database.


The endprojent() function closes the project database and deallocates
resources when processing is complete. It is permissible, though possibly
less efficient, for the process to call more project functions after
calling endprojent().


The getprojbyname() function searches the project database for an entry
with the project name specified by the character string name.


The getprojbyid() function searches the project database for an entry
with the (numeric) project ID specified by projid.


The getdefaultproj() function first looks up the project key word in the
user_attr database used to define user attributes in restricted Solaris
environments. If the database is available and the keyword is present,
the function looks up the named project, returning NULL if it cannot be
found or if the user is not a member of the named project. If absent, the
function looks for a match in the project database for the special
project user.username. If no match is found, or if the user is excluded
from project user.username, the function looks at the default group entry
of the passwd database for the user, and looks for a match in the project
database for the special name group.groupname, where groupname is the
default group associated with the password entry corresponding to the
given username. If no match is found, or if the user is excluded from
project group.groupname, the function returns NULL. A special project
entry called 'default' can be looked up and used as a last resort, unless
the user is excluded from project 'default'. On successful lookup, this
function returns a pointer to the valid project structure. By convention,
the user must have a default project defined on a system to be able to
log on to that system.


The inproj() function checks if the user specified by username is able to
use the project specified by projname. This function returns 1 if the
user belongs to the list of project's users, if there is a project's
group that contains the specified user, if project is a user's default
project, or if project's user or group list contains "*" wildcard. In
all other cases it returns 0.


The getprojidbyname() function searches the project database for an entry
with the project name specified by the character string name. This
function returns the project ID if the requested entry is found;
otherwise it returns -1.


The fgetprojent() function, unlike the other functions described above,
does not use nsswitch.conf; it reads and parses the next line from the
stream f, which is assumed to have the format of the project(5) file.
This function returns the same values as getprojent().


The getprojent(), getprojbyname(), getprojbyid(), getdefaultproj(), and
inproj() functions are reentrant interfaces for operations with the
project database. These functions use buffers supplied by the caller to
store returned results and are safe for use in both single-threaded and
multithreaded applications.


Reentrant interfaces require the additional arguments proj, buffer, and
bufsize. The proj argument must be a pointer to a struct project
structure allocated by the caller. On successful completion, the function
returns the project entry in this structure. Storage referenced by the
project structure is allocated from the memory provided with the buffer
argument, which is bufsize bytes in size. The content of the memory
buffer could be lost in cases when these functions return errors.


For enumeration in multithreaded applications, the position within the
enumeration is a process-wide property shared by all threads. The
setprojent() function can be used in a multithreaded application but
resets the enumeration position for all threads. If multiple threads
interleave calls to getprojent(), the threads will enumerate disjoint
subsets of the project database. The inproj(), getprojbyname(),
getprojbyid(), and getdefaultproj() functions leave the enumeration
position in an indeterminate state.

RETURN VALUES


Project entries are represented by the struct project structure defined
in <project.h>.

struct project {
char *pj_name; /* name of the project */
projid_t pj_projid; /* numerical project id */
char *pj_comment; /* project comment */
char **pj_users; /* vector of pointers to
project user names */
char **pj_groups; /* vector of pointers to
project group names */
char *pj_attr; /* project attributes */
};


The getprojbyname() and getprojbyid() functions each return a pointer to
a struct project if they successfully locate the requested entry;
otherwise they return NULL.


The getprojent() function returns a pointer to a struct project if it
successfully enumerates an entry; otherwise it returns NULL, indicating
the end of the enumeration.


The getprojidbyname() function returns the project ID if the requested
entry is found; otherwise it returns -1 and sets errno to indicate the
error.


When the pointer returned by the reentrant functions getprojbyname(),
getprojbyid(), and getprojent() is non-null, it is always equal to the
proj pointer that was supplied by the caller.


Upon failure, NULL is returned and errno is set to indicate the error.

ERRORS


The getprojent(), getprojbyname(), getprojbyid(), inproj(),
getprojidbyname(), fgetprojent(), and getdefaultproj() functions will
fail if:

EINTR
A signal was caught during the operation.


EIO
An I/O error has occurred.


EMFILE
There are OPEN_MAX file descriptors currently open in the
calling process.


ENFILE
The maximum allowable number of files is currently open in the
system.


ERANGE
Insufficient storage was supplied by buffer and bufsize to
contain the data to be referenced by the resulting project
structure.


These functions can also fail if the name service switch does not specify
valid project(5) name service sources. In the case of an incompletely
configured name service switch configuration, getprojbyid() and other
functions can return error values other than those documented above.
These conditions usually occur when the nsswitch.conf file indicates that
one or more name services is providing entries for the project database
when that name service does not actually make a project table available.

USAGE


When compiling multithreaded applications, see Intro(3), Notes On
Multithreaded Applications.


Use of the enumeration interface getprojent() is discouraged. Enumeration
is supported for the project file, NIS, and LDAP but in general is not
efficient. The semantics of enumeration are discussed further in
nsswitch.conf(5).

ATTRIBUTES


See attributes(7) for descriptions of the following attributes:


+--------------------+------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+------------------+
|Interface Stability | Evolving |
+--------------------+------------------+
|MT-Level | See Description. |
+--------------------+------------------+

SEE ALSO


Intro(3), sysconf(3C), libproject(3LIB), project_walk(3PROJECT),
nsswitch.conf(5), project(5), attributes(7)

April 5, 2004 GETPROJENT(3PROJECT)