"Alex V . Melnikov" wrote: > > Hello, people! > I have read pam-modules development documentation > and understood next, if i want to communicate with > user, i should use some pam interface, isn't it? > But standard C function, like printf and scanf, > works too. > > Can i use it or not? No, in short. Printf/scanf works only if your module called by something like login, telnetd, su etc. Them will not work for e.g. xdm's login or any other graphical login. Pam interface (namely, pam conversation mechanism) designed especially so that any pam module can work with any pamified application regardless of what is the "display" term means for that application. I.e. it is applications's responsibility to display pam's messages on the way known to that app, and to ask user the question pam module wanted to ask. > Thanks. > > Alex V. Melnikov. > Regards, Michael.