pw_mapping(3)pw_mapping(3)NAME
pw_nametoid, pw_idtoname, gr_nametoid, gr_idtoname - Map between user
and group names and IDs (Enhanced Security)
SYNOPSIS
#include <sys/types.h> #include <prot.h>
uid_t pw_nametoid(
char *name ); char *pw_idtoname(
uid_t id ); gid_t gr_nametoid(
char *name ); char *gr_idtoname(
gid_t id );
LIBRARY
Enhanced Security Library (libsecurity)
PARAMETERS
Specifies the user (pw_nametoid()) or group (gr_nametoid()) name.
Specifies the user (pw_idtoname()) or group (gr_idtoname()) ID.
DESCRIPTION
The mapping functions provide an efficient mapping between user and
group names and identifiers (IDs). These functions maintain a separate
binary database, which is automatically updated each time the functions
encounter a changed /etc/passwd or /etc/group file. Also, these func‐
tions do not interfere with the behavior of the getpwent() and get‐
grent() functions, and are thus used by the protected password database
functions, which must frequently convert between names and identifiers
but may not disrupt an application's use of password mapping functions.
NOTES
Programs using these functions must be compiled with -lsecurity.
RETURN VALUES
Functions returning character strings return Null on failure, and a
pointer to a string in an internal (that is, internal to the functions)
memory area containing the user or group name on success. Functions
returning integers return a nonnegative user or group ID on success, or
a value of -1 on failure.
FILES
System password file. System group file.
SEE ALSO
Functions: getgrent(3), getprpwent(3), getpwent(3)pw_mapping(3)