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+#$EPIC: wait.txt,v 1.5 2006/08/30 19:28:30 sthalik Exp $
+======Synopsis:======
+__wait__ [for] [%<process>]|[-cmd <command>] \\
+__wait__ for =<fd>
+======Description:======
+__WAIT__ is a convenient means for executing a series of commands and
+ensuring that those commands are run in the desired sequence.  The
+command can make the client wait for the completion of server or
+subprocess output.
+Use of __WAIT__ is almost always avoidable, see section Other Notes below.
+The simplest form is __WAIT__ with no arguments.  When run after a server
+query, the client will not execute further commands (within an alias;
+does not apply to the input line) until all server output has been
+received.
+If used as /wait for, it will execute the command, and halt until a server
+reply is detected.
+When waiting on an [[exec command|EXEC]]ed subprocess, the client will
+block until the subprocess has completed.  This effectively disables the
+the entire client (and can even cause it to ping timeout from the
+server).
+The last form allows for a series of commands to be executed in no
+particular order.  This is most useful when a particular command needs
+to be issued, but subsequent commands don't rely on its contents or
+timing.
+When waiting on an [[exec command|EXEC]]ed subprocess _with_ a -cmd
+option, the command will return immediately, and the command will be
+executed when the process finishes.  This will be as if the [[exec
+command|EXEC]] command had been given a -end flag with the same command.
+__WAIT for =fd__ waits for a [[DCC]] or $[[connect function|connect]]
+identified by //fd// to be completed.
+======Options:======
+   -cmd <commands>   execute the given commands at the end of the alias/exec.
+======Examples:======
+To add a header and footer to a channel's ban list:
+      alias banlist {
+         echo *** Begin ban list for #blah (generated $stime($time()))
+         mode #blah +b
+         wait
+         echo *** End ban list for #blah
+      }
+To run a subprocess, and wait before doing anything else:
+      alias localusers {
+         echo *** Getting list of local users...
+         exec -name who who
+         wait %who
+         echo *** Finished subshell `who' listing
+      }
+The second command will actually finish before the first:
+      alias backwards {
+         wait -cmd echo this appears last
+         echo this appears first
+      }
+======Known Issues:======
+__WAIT__ turns a non-blocking operation into a blocking one. This
+is almost always a bad idea, as it prevents the client from doing
+other things. At best, it is inefficient, at worst it can completely
+lock up the client. Use with care, and avoid if possible.
+======Other Notes:======
+If multiple __WAIT__s are pending at once, they will all return once the last
+one is completed, to ensure that no data is lost.
+Using __WAIT__ for server queries is useful.  However, there are often times
+then it is not the most efficient way to do something.  When possible,
+hooking server numerics that marks the end of a message is preferred, as
+it is generally more reliable.
+Using __wait__(5) or __wait__(5) __for__ and /[[redirect]] is a Bad Thing(tm),
+so don't do it.