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Subsections

• Synopsis
• Description
• Options
• Notes
• Diagnostics
• Examples
• Bugs
• See also
• Author

rai

Check in AIPS++ sources by invoking ai (p) remotely via ssh.

Synopsis

rai [

options for

ai]

Description

rai is an ssh-based front-end to ai (p). It checks in files by transmitting them to the AIPS++ master host via ssh as a gzip'd tar file and running ai there. This is provided as an alternative to invoking ai directly on a machine on which the AIPS++ master directory is remotely NFS mounted.

In order to use rai a programmer must have an account on aips2.nrao.edu and it must be set up for ssh access from the local host via a suitable entry in the .ssh/authorized_keys file (.ssh/authorized_keys2 for ssh2 based access). The programmer must also have an up-to-date AIPS++ workspace on aips2.nrao.edu and it must be rooted at $HOME/aips++ (see mktree (p)). Visit the Using SSH page for more details on using ssh in AIPS++.

Options

Refer to the options for ai (p). rai itself has no options.

Notes

• rai handles directories as well as files.

• rai is faster than ai because
  • It only has to do one file transfer rather than two.

  • It transfers files in compressed form.

  • Although it needs to invoke ssh two or three times the overhead involved in this is less than that of one automount of a remote filesystem.

• When accessing aips2.nrao.edu via ssh the programmer's login initialization scripts (e.g. .bashrc, .cshrc, .esrc, .login, .profile, .rcrc, .tcshrc) must not consume stdin or write to stdout or stderr.

• Where the account name on the aips2.nrao.edu differs from the local account name an environment variable may be used to translate between them:

     AUID="<remotename>"
  

  The .ssh/authorized_keys (.ssh/authorized_keys2 for ssh2) file for the remotename account on aips2.nrao.edu should have an entry for each machine you may want to use remotely.

  you will need to run ssh-keygen and put the generated key in the .ssh/authorized_keys on aips2.nrao.edu

• rai is not failsafe in the way that ai is failsafe. It has no way of determining whether a checkin succeeded and so provides no guarantees one way or the other. This arises because of the difficulty in recovering status returns from complicated command sequences executed by ssh.

  If a checkin fails the error message from ci will be visible on stderr but rai will not catch an error return. The only course of action would be to log in to aips2.nrao.edu and clean up manually.

  For this reason, rai never deletes files from the local workspace but simply removes the write permission from them (unless invoked with the -l option) - even if the checkin failed. It is left to the programmer to decide whether the checkin succeeded and delete them explicitly.

  rai does delete files from the aips2.nrao.edu workspace if the checkin succeeded.

• rai exhibits the following differencees from ai by virtue of the fact that it runs ai remotely through an ssh:
  • When ci says to

       enter description, terminated with single '.' or end of file:
    

    you must terminate with a single ``.'' and not use ^D. The reason is simply that ^D means ``end-of-file'' to the ssh as well as ci, so if you use ^D when checking in multiple files ci will not accept change messages for succeeding files.

  • There may be noticable delays in entering the change message.

• ssh is used as the transfer agent rather than ftp since the latter requires a password to be supplied for each remote access.

Diagnostics

Status return values
0: success (returned from ai_master)
1: initialization error, no checkin

Examples

The command

   rai -au Foo.cc

would check in Foo.cc from the current directory into the corresponding AIPS++ master repository, updating the slave and plain-text copies in the process. The copy of Foo.cc in the current directory would not be deleted but it's write permission would be removed. If the checkin succeeded it would be appropriate to manually delete the file

   rm Foo.cc

If the checkin failed then it would be necessary to log in to aips2.nrao.edu and recover manually.

Bugs

• Not all of the ai (p) options are supported yet due to setuid issues.

See also

The manual page for ci(1), the RCS checkin command.
The GNU manual page for gzip(1).
The unix manual page for ftp(1).
The unix manual page for ping(1).
The unix manual page for ssh(1).
ai (p), AIPS++ code checkin utility.
ao (p), AIPS++ code checkout utility.
au (p), AIPS++ code update utility.
mktree (p) create AIPS++ directory hierarchy.
rao (p), invoke ao remotely via ssh(1).
rau (p), update AIPS++ sources from the master via ssh(1).

Author

Original: 1996/08/06 by Mark Calabretta, ATNF.