# yum info nail
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 * addons: centos.ustc.edu.cn
 * base: centos.ustc.edu.cn
 * extras: centos.ustc.edu.cn
 * rpmforge: ftp-stud.fht-esslingen.de
 * updates: centos.ustc.edu.cn
Installed Packages
Name       : nail
Arch       : x86_64
Version    : 12.3
Release    : 4.el5.rf
Size       : 612 k
Repo       : installed
Summary    : Enhanced implementation of the mailx command
URL        : http://nail.sourceforge.net/
License    : BSD
Description: Nail is an enhanced mail command, which provides the functionality
           : of the POSIX mailx command. It is derived from Berkeley Mail.
           :
           : Additionally to the POSIX features, nail can work with Maildir/ e-mail
           : storage format (as well as mailboxes), supports IMAP, POP3 and SMTP
           : procotols (including over SSL) to operate with remote hosts, handles mime
           : types and different charsets. There are a lot of other useful features,
           : see nail.html in the documentation.
           :
           : And as its ancient analogues, nail can be used as a mail script language,
           : both for sending and receiving mail.