pam_get_user 3 Linux-PAM Manual pam_get_user get user name #include <security/pam_modules.h> int pam_get_user const pam_handle_t *pamh const char **user const char *prompt The pam_get_user function returns the name of the user specified by pam_start3 . If no user was specified it returns what pam_get_item (pamh, PAM_USER, ... ); would have returned. If this is NULL it obtains the username via the pam_conv3 mechanism, it prompts the user with the first non-NULL string in the following list: The prompt argument passed to the function. What is returned by pam_get_item (pamh, PAM_USER_PROMPT, ... ); The default prompt: "login: " By whatever means the username is obtained, a pointer to it is returned as the contents of *user. Note, this memory should not be free()'d or modified by the module. This function sets the PAM_USER item associated with the pam_set_item3 and pam_get_item3 functions. PAM_SUCCESS User name was successful retrieved. PAM_SYSTEM_ERR A NULL pointer was submitted. PAM_CONV_ERR The conversation method supplied by the application failed to obtain the username. PAM_BUF_ERR Memory buffer error. PAM_ABORT Error resuming an old conversation. PAM_CONV_AGAIN The conversation method supplied by the application is waiting for an event. pam_end3 , pam_get_item3 , pam_set_item3 , pam_strerror3