#include <security/pam_appl.h>
It should be noted that the effective uid, geteuid(2). of the application should be of sufficient privilege to perform such tasks as creating or mounting the user's home directory for example.
The flags argument is the binary or of zero or more of the following values:
PAM_SILENT
PAM_ABORT
PAM_BUF_ERR
PAM_SESSION_ERR
PAM_SUCCESS
pam_close_session(3), pam_strerror(3)