pam_get_user Subroutine
Purpose
Gets the user's name from the PAM handle or through prompting for input.
Library
PAM Library (libpam.a)
Syntax
#include <security/pam_appl.h>
int pam_get_user (
pam_handle_t *pamh,
char **user,
const char *prompt);
Description
The pam_get_user subroutine returns the user name currently stored in the PAM handle, pamh. If the user name has not already been set through pam_start() or pam_set_item(), the subroutine displays the string specified by prompt, to prompt for the user name through the conversation function. If prompt is NULL, the value of PAM_USER_PROMPT set through a call to pam_set_item() is used. If both prompt and PAM_USER_PROMPT are NULL, PAM defaults to use the following string:
Please enter user name:
After the user name has been retrieved, it is set in the PAM handle and is also returned to the caller in the user argument. The caller should not change or free user, as cleanup will be handled by pam_end().
Parameters
| Item | Description |
|---|---|
| pamh | The PAM handle representing the current user authentication session. This handle is obtained by a call to pam_start(). |
| user | The user name retrieved from the PAM handle or provided by the user. |
| prompt | The prompt to be displayed if a user name is required and has not been already set. |
Return Values
Upon successful completion, pam_get_user returns PAM_SUCCESS. Also, a reference to the user name is returned in user. If the routine fails, either PAM_SYSTEM_ERR, PAM_BUF_ERR, or PAM_CONV_ERR is returned, depending on what the actual error was, and a NULL reference in user is returned.
Error Codes
| Item | Description |
|---|---|
| PAM_SYSTEM_ERR | A system error occurred. |
| PAM_BUF_ERR | A memory error occurred. |
| PAM_CONV_ERR | A conversation error or failure. |