sudo -S not working

[fabriziors]

Hi I'm trying to use automatic login with sudo like this:

echo "<mypassword>\n" | sudo -S su - <myuser> or
cat pass.txt | sudo -S su - <myuser>

but in both case I'm getting the same error:

stty: standard input: Invalid argument
ksh: <stdin>[1]: <mypassword>: not found


my linux version:
$ uname -a
Linux <host> 2.6.9-89.33.1.EL #1 Mon Nov 15 18:52:05 EST 2010 x86_64 x86_64 x86_64 GNU/Linux

my sudo version:
$ sudo -V
Sudo version 1.6.7p5

my terminal settings
$ stty -a
speed 38400 baud; rows 42; columns 145; line = 0;
intr = ^C; quit = ^\; erase = ^H; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W;
lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 -hupcl -cstopb cread -clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc -ixany -imaxbel
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke



Someone could help me with that ?
i'll really appreciate


Tks,
Fabrizio

[meton_magis]

I'm not quite understanding how you're trying to login.

You are trying to auto-login on a tty login prompt??
I don't think that is possible.

If you are trying to auto-login to an X windows session, I know gnome has a method for that.

If you want to auto login from 1 user to another via script, both sudo and su require stdin to be a tty.

[ved]

Read this link it help you
Personal Fedora 13 Installation Guide