parallel: EXAMPLE: Start editor with filenames from stdin (standard input).

parallel: EXAMPLE: GNU Parallel as queue system/batch manager.

doc/FUTURE_IDEAS

@@ -75,6 +75,38 @@ find music-files -type f | parallel -j+0 -S :,server1,server2 \
 # sem
 # --retry
 
+(echo a1.txt; echo b1.txt; echo c1.txt; echo a2.txt; echo b2.txt; echo c2.txt;)| \
+parallel -X -N 3 my-program --file={}
+
+(echo a1.txt; echo b1.txt; echo c1.txt; echo d1.txt; echo e1.txt; echo f1.txt;)| \
+parallel -X my-program --file={}
+
+# First job controls the tty
+# -u needed because output should not be saved for later
+
+find . -type f | parallel -uXj1 vim
+find . -type f | parallel -uXj1 emacs
+
+# If you have 1000 files only one contains 'foobar'
+# stop when this one is found
+
+find . -type f | parallel  grep -l foobar | head -1
+
+
+# To test a list of hosts are up and pingable save this
+# to a file called machinesup
+
+#!/usr/bin/parallel --shebang --no-run-if-empty ping -c 3 {} >/dev/null 2>&1
+
+google.com
+yahoo.com
+nowhere.gone
+
+# Then:
+#   chmod 755 machinesup
+#   ./machinesup || echo Some machines are down
+
+
 
 =head1 YouTube video
 

doc/release_new_version

@@ -116,38 +116,26 @@ cc:Peter Simons <simons@cryp.to>, Sandro Cazzaniga <kharec@mandriva.org>,
    Tim Cuthbertson <tim3d.junk@gmail.com>, Ludovic Courtès <ludo@gnu.org>,
    Markus Ammer <mkmm@gmx-topmail.de>, Pavel Nuzhdin <pnzhdin@gmail.com>,
    Phil Sung <psung@alum.mit.edu>, Michael Shigorin <mike@altlinux.org>,
-   Andrew McFague <amcfague@wgen.net>, Steven M. Christensen <sunfreeware@gmail.com>
+   Andrew McFague <amcfague@wgen.net>, Steven M. Christensen <sunfreeware@gmail.com>,
+   Chris Howey <howeyc@gmail.com>
 
-Subject: GNU Parallel 20100922 released
+Subject: GNU Parallel 2010XXXX released
 
-GNU Parallel 20100922 has been released. It is available for
+GNU Parallel 2010XXXX has been released. It is available for
 download at: http://ftp.gnu.org/gnu/parallel/
 
 New in this release:
 
+* FreeBSD port. Thanks to Chris Howey <howeyc at gmail dot com>
+
+* First review on print:
+  http://www.linux-magazine.com/Issues/2010 Nov 2010
+
+Old in this release:
+
 * See GNU Parallel live at FSCONS 2010-11-07:
   http://www.fscons.org/fs/gnu-parallel
 
-* Untested Debian and xUbuntu packages available through OpenSUSE
-  build service:
-  https://build.opensuse.org/package/show?package=parallel&project=home%3Atange
-
-* Using --retries a job will be retried on another computer if it
-  fails. This is useful if some jobs fail for no apparent reason (such
-  as network failure).
-
-* BSD xargs -o (open /dev/tty) is now default for the job running in
-  foreground. Useful for interactive commands like:
-  ls | parallel -Xuj1 vi
-
-* GNU sql now supports SQLite.
-
-* Renamed .dburl.aliases to .sql/aliases and /etc/sql/aliases.
-
-* GNU sql now support --list-tables
-
-* Alias for DBURL can contain '?query' part with %-quoting.
-
 
 = About GNU Parallel =
 

src/parallel

@@ -462,7 +462,8 @@ with all the arguments.
 
 Support for B<-m> with B<--sshlogin> is limited and may fail.
 
-See also B<-X> for context replace.
+See also B<-X> for context replace. If in doubt use B<-X> as that will
+most likely do what is needed.
 
 
 =item B<--progress>
@@ -843,13 +844,19 @@ Implies B<--semaphore>.
 
 =item B<-X>
 
-xargs with context replace. This works like B<-m> except if B<{}> is part
+Multiple arguments with context replace. Insert as many arguments as
-of a word (like I<pic{}.jpg>) then the whole word will be
+the command line length permits. If B<{}> is not used the arguments
-repeated. Normally B<-X> will do the right thing, whereas B<-m> can
+will be appended to the line.  If B<{}> is used as part of a word
-give surprising results if B<{}> is used as part of a word.
+(like I<pic{}.jpg>) then the whole word will be repeated. If B<{}> is
+used multiple times each B<{}> will be replaced with the arguments.
+
+Normally B<-X> will do the right thing, whereas B<-m> can give
+unexpected results if B<{}> is used as part of a word.
 
 Support for B<-X> with B<--sshlogin> is limited and may fail.
 
+See also B<-m>.
+
 
 =item B<--exit>
 
@@ -1370,6 +1377,36 @@ same time:
   seq 1 3 | parallel sem --id mymutex sed -i -e 'i{}' myfile
 
 
+=head1 EXAMPLE: Start editor with filenames from stdin (standard input)
+
+You can use GNU Parallel to start interactive programs like emacs or vi:
+
+B<cat filelist | parallel -uXj1 emacs>
+
+B<cat filelist | parallel -uXj1 vi>
+
+If there are more files than will fit on a single command line, the
+editor will be started again with the remaining files.
+
+
+=head1 EXAMPLE: GNU Parallel as queue system/batch manager
+
+GNU Parallel can work as a simple job queue system or batch manager.
+The idea is to put the jobs into a file and have GNU Parallel read
+from that continuously. As GNU Parallel will stop at end of file we
+use tail to continue reading:
+
+B<echo >>B<jobqueue>; B<tail -f jobqueue | parallel>
+
+To submit your jobs to the queue:
+
+B<echo my_command my_arg >>>B< jobqueue>
+
+You can of course use B<-S> to distribute the jobs to remote
+computers:
+
+B<echo >>B<jobqueue>; B<tail -f jobqueue | parallel -S ..>
+
 =head1 QUOTING
 
 For more advanced use quoting may be an issue. The following will