04-23-2008
The problem is that you have two things which want to read standard input. Your while loop reads one line at a time, but the dbSomething (or something else in that script) slurps in as much as it can get, the first time it runs.
So we make them read from different file descriptors. That's what the exec does: it connects the input file to file descriptor 3 (instead of 0, standard input; 1 and 2 are standard out and standard error, respectively) and then we modify the while loop to expect its input from that file descriptor. Then at the end we close fd3 when we're done with it, with another exec.
exec, like set, has two different uses. One is to replace the current shell with another process (exec programname); the other is to manipulate the current shell's file descriptors. We use the latter functionality here.
Probably you could redirect dbSomething to read from /dev/null instead -- that would be a simpler change, all right, but I wasn't particularly in the mood to speculate on whether that will work with that particular program or not.
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LEARN ABOUT SUSE
installsieve
INSTALLSIEVE(1) General Commands Manual INSTALLSIEVE(1)
*
NAME
installsieve - user utility for managing sieve scripts
SYNOPSIS
installsieve
DESCRIPTION
installsieve is a utility that allows users to manage their sieve scripts kept on the server.
OPTIONS
-v <name> View script with the given name. The script if retrieved sucessfully is output to standard output.
-l List all of the scripts currently on the server. If one of the scripts is active a arrow is printed indicating that it is the active
script.
-p <port> Port to connect to. If left off this defaults to "sieve" as defined in /etc/services.
-i <file> Install a file onto the server. If a script with the same name already exists on the server it is overwritten. Upon sucessfully
putting the script on the server the script is set active. If <file> has the extension .script it is chopped when put on the server since
sieve names may not contain a '.'.
-a <name> Set <name> as the active script. The list of available names can be obtained from the '-l' option..
-d <name> Delete the sieve script on the server with <name>.
-m <mechanism> Force installsieve to use <mechanism> for authentication. If not specified the strongest authentication mechanism is chosen.
-g <name> Get the sieve script with <name> and save it to disk with a ".script" extension. If a file with that name already exists it is
overwritten.
-u <user> Userid/Authname to use for authentication; by default, the current user.
CMU
Project Cyrus INSTALLSIEVE(1)