SSH, The Secure Shell: The Definitive Guide, 2nd Edition

Miscellaneous Clients

Several other clients are included in addition to ssh and scp :

• sftp , an ftp-like client

• slogin, a link to ssh, analogous to the rlogin program

2.7.1 sftp

The scp command is convenient and useful, but many users are already familiar with FTP (File Transfer Protocol), a more widely used technique for transferring files on the Internet.^[10] sftp is a separate file-transfer tool layered on top of SSH. The OpenSSH sftp can run over either SSH-1 or SSH-2, whereas the Tectia version runs over SSH-2 only due to implementation details.

sftp has several advantages:

• It is secure, using an SSH-protected channel for data transfer.

• Multiple commands for file copying and manipulation can be invoked within a single sftp session, whereas scp opens a new session each time it is invoked.

• It can be scripted using the familiar ftp command language.

• In other software applications that run an FTP client in the background, you can try substituting sftp, thus securing the file transfers of that application. You might need to run an agent, however, since programs that normally invoke ftp might not recognize the sftp passphrase prompt, or they might expect you to have suppressed FTP’s password prompt (using a .netrc file, for example).

Anyone familiar with FTP will feel right at home with sftp, but sftp has some additional features of note:

• Command-line editing using GNU Emacs-like keystrokes (Control-B for backward character, Control-E for end of line, and so forth).^[11]

• Wildcards for matching ...