Using KWrite to find and replace a character with a CRLF (Carriage Return/Line Feed)

Occasionally I need to edit a long string and replace the space character with a CRLF and some text. Even though I was sure the KDE editor KWrite could do that, I had never bothered to find out how. Today I finally bit the bullet. It’s not difficult, of course. To show you how it is done, I’ll give an actual example…

I wanted to edit in KWrite the single line of text shown below. (Not that it’s relevant to the subject of this post, but the line was a command to the Gentoo package manager to install a long list of packages, and I wanted to split it into separate commands in order to install each package individually.)

emerge -vD1 --backtrack=30 media-video/dvdrip:0 dev-vcs/git:0 dev-vcs/subversion:0 net-print/foomatic-db-engine:0 app-antivirus/clamtk:0 dev-perl/XML-SAX:0 dev-perl/X11-Protocol:0 dev-perl/Goo-Canvas:0 dev-perl/Readonly:0 dev-perl/File-Find-Rule:0 dev-perl/Net-SSLeay:0 dev-perl/XML-LibXML:0 dev-perl/HTTP-Message:0 dev-perl/Digest-SHA1:0 dev-perl/XML-XPath:0 dev-perl/File-Which:0 dev-perl/Authen-SASL:0 dev-perl/glib-perl:0 dev-perl/prefork:0 dev-perl/IO-Socket-SSL:0 dev-perl/Exception-Class:0 dev-perl/Proc-Simple:0 dev-perl/WWW-Mechanize:0 dev-perl/gnome2-canvas:0 dev-perl/gnome2-vfs-perl:0 dev-perl/IO-String:0 dev-perl/HTML-Tagset:0 dev-perl/Carp-Clan:0 dev-perl/Pod-Spell:0 dev-perl/Sane:0 dev-perl/TermReadKey:0 dev-perl/HTTP-Date:0 dev-perl/Encode-Locale:0 dev-perl/Event-RPC:0 dev-perl/File-HomeDir:0 dev-perl/Bit-Vector:0 dev-perl/gnome2-wnck:0 dev-perl/File-Copy-Recursive:0 dev-perl/Text-Unidecode:0 dev-perl/Unicode-EastAsianWidth:0 dev-perl/extutils-pkgconfig:0 dev-perl/Clone:0 dev-perl/Event-ExecFlow:0 dev-perl/B-Keywords:0 dev-perl/PDF-API2:0 dev-perl/HTTP-Negotiate:0 dev-perl/HTML-Form:0 dev-perl/extutils-depends:0 dev-perl/PlRPC:0 dev-perl/libwww-perl:0 dev-perl/gtk2-perl:0 dev-perl/File-MimeInfo:0 dev-perl/Font-TTF:0 dev-perl/libintl-perl:0 dev-perl/List-MoreUtils:0 dev-perl/Log-Log4perl:0 dev-perl/XML-DOM:0 dev-perl/HTML-Parser:0 dev-perl/Try-Tiny:0 dev-perl/XML-Twig:0 dev-perl/Gtk2-Ex-Simple-List:0 dev-perl/LWP-MediaTypes:0 dev-perl/LWP-Protocol-https:0 dev-perl/XML-Simple:0 dev-perl/Pango:0 dev-perl/set-scalar:0 dev-perl/Gtk2-Unique:0 dev-perl/Params-Util:0 dev-perl/Net-Daemon:0 dev-perl/GSSAPI:0 dev-perl/XML-NamespaceSupport:0 dev-perl/PPI:0 dev-perl/Proc-ProcessTable:0 dev-perl/String-Format:0 dev-perl/Date-Calc:0 dev-perl/XML-Parser:0 dev-perl/Email-Address:0 dev-perl/Class-Data-Inheritable:0 dev-perl/Email-Simple:0 dev-perl/JSON:0 dev-perl/gnome2-perl:0 dev-perl/XML-SAX-Base:0 dev-perl/Net-SMTP-SSL:0 dev-perl/Gtk2-ImageView:0 dev-perl/IO-HTML:0 dev-perl/WWW-RobotRules:0 dev-perl/Digest-HMAC:0 dev-perl/HTTP-Cookies:0 dev-perl/DBI:0 dev-perl/URI:0 dev-perl/Text-Iconv:0 dev-perl/gtk2-ex-formfactory:0 dev-perl/Email-Date-Format:0 dev-perl/libxml-perl:0 dev-perl/XML-SAX-Writer:0 dev-perl/XML-Filter-BufferText:0 dev-perl/Number-Compare:0 dev-perl/XML-RegExp:0 dev-perl/Email-LocalDelivery:0 dev-perl/config-general:0 dev-perl/HTTP-Daemon:0 dev-perl/File-Listing:0 dev-perl/Devel-StackTrace:0 dev-perl/Set-IntSpan:0 dev-perl/Cairo:0 dev-perl/Email-FolderType:0 dev-perl/XML-Handler-YAWriter:0 dev-perl/Archive-Zip:0 dev-perl/Net-DBus:0 dev-perl/DBD-mysql:0 dev-perl/AnyEvent:0 dev-perl/perltidy:0 dev-perl/Locale-gettext:0 dev-perl/Sort-Naturally:0 dev-perl/Net-HTTP:0 dev-perl/Perl-Critic:0 media-gfx/gscan2pdf:0 media-libs/exiftool:0 perl-core/CPAN-Meta-Requirements:0 virtual/perl-CPAN-Meta-Requirements:0 perl-core/IPC-Cmd:0 virtual/perl-IPC-Cmd:0 perl-core/Storable:0 virtual/perl-Storable:0 perl-core/File-Spec:0 virtual/perl-File-Spec:0 perl-core/CPAN-Meta:0 virtual/perl-CPAN-Meta:0 perl-core/Getopt-Long:0 virtual/perl-Getopt-Long:0 perl-core/Locale-Maketext-Simple:0 virtual/perl-Locale-Maketext-Simple:0 perl-core/ExtUtils-Manifest:0 virtual/perl-ExtUtils-Manifest:0 perl-core/Pod-Simple:0 virtual/perl-Pod-Simple:0 perl-core/CPAN-Meta-YAML:0 virtual/perl-CPAN-Meta-YAML:0 perl-core/Encode:0 virtual/perl-Encode:0 perl-core/Compress-Raw-Bzip2:0 virtual/perl-Compress-Raw-Bzip2:0 perl-core/Module-Load:0 virtual/perl-Module-Load:0 perl-core/Archive-Tar:0 virtual/perl-Archive-Tar:0 perl-core/Scalar-List-Utils:0 virtual/perl-Scalar-List-Utils:0 perl-core/ExtUtils-CBuilder:0 virtual/perl-ExtUtils-CBuilder:0 perl-core/Parse-CPAN-Meta:0 virtual/perl-Parse-CPAN-Meta:0 perl-core/version:0 virtual/perl-version:0 perl-core/Digest-SHA:0 virtual/perl-Digest-SHA:0 perl-core/Module-Load-Conditional:0 virtual/perl-Module-Load-Conditional:0 perl-core/Compress-Raw-Zlib:0 virtual/perl-Compress-Raw-Zlib:0 perl-core/ExtUtils-Install:0 virtual/perl-ExtUtils-Install:0 perl-core/IO:0 virtual/perl-IO:0 perl-core/Time-Local:0 virtual/perl-Time-Local:0 perl-core/Module-CoreList:0 virtual/perl-Module-CoreList:0 perl-core/Digest-MD5:0 virtual/perl-Digest-MD5:0 perl-core/JSON-PP:0 virtual/perl-JSON-PP:0 perl-core/ExtUtils-ParseXS:0 virtual/perl-ExtUtils-ParseXS:0 perl-core/File-Temp:0 virtual/perl-File-Temp:0 perl-core/Params-Check:0 virtual/perl-Params-Check:0 perl-core/Module-Metadata:0 virtual/perl-Module-Metadata:0 perl-core/Sys-Syslog:0 virtual/perl-Sys-Syslog:0 perl-core/IO-Compress:0 virtual/perl-IO-Compress:0 perl-core/Test-Harness:0 virtual/perl-Test-Harness:0

With the above line of text in a KWrite window, I did the following:

1. I selected Edit > Replace… from the KWrite menu.

2. At the bottom of the KWrite window, I changed the Mode from ‘Plain text’ to ‘Regular expression’.

3. I clicked in the ‘Find’ box and pressed the Space bar to enter a space character.

4. I clicked in the ‘Replace’ box and entered the following text (note that there is ‘\n’ at the beginning and a space at the end):

\nemerge -vD1 --backtrack=30 

The ‘\n‘ represents a CRLF (Carriage Return plus Line Feed).

5. I ticked ‘Selection only’.

6. With the mouse I selected the text in which I wanted to make the replacement, i.e. I selected from (and including) the space following the first package (media-video/dvdrip:0) all the way to the end of the line.

7. I clicked on ‘Replace All’.

The result looked like this:

emerge -vD1 --backtrack=30 media-video/dvdrip:0
emerge -vD1 --backtrack=30 dev-vcs/git:0
emerge -vD1 --backtrack=30 dev-vcs/subversion:0
emerge -vD1 --backtrack=30 net-print/foomatic-db-engine:0
emerge -vD1 --backtrack=30 app-antivirus/clamtk:0
emerge -vD1 --backtrack=30 dev-perl/XML-SAX:0
emerge -vD1 --backtrack=30 dev-perl/X11-Protocol:0
emerge -vD1 --backtrack=30 dev-perl/Goo-Canvas:0
emerge -vD1 --backtrack=30 dev-perl/Readonly:0
emerge -vD1 --backtrack=30 dev-perl/File-Find-Rule:0
emerge -vD1 --backtrack=30 dev-perl/Net-SSLeay:0
emerge -vD1 --backtrack=30 dev-perl/XML-LibXML:0
emerge -vD1 --backtrack=30 dev-perl/HTTP-Message:0
emerge -vD1 --backtrack=30 dev-perl/Digest-SHA1:0
emerge -vD1 --backtrack=30 dev-perl/XML-XPath:0
emerge -vD1 --backtrack=30 dev-perl/File-Which:0
emerge -vD1 --backtrack=30 dev-perl/Authen-SASL:0
emerge -vD1 --backtrack=30 dev-perl/glib-perl:0
emerge -vD1 --backtrack=30 dev-perl/prefork:0
emerge -vD1 --backtrack=30 dev-perl/IO-Socket-SSL:0
emerge -vD1 --backtrack=30 dev-perl/Exception-Class:0
emerge -vD1 --backtrack=30 dev-perl/Proc-Simple:0
emerge -vD1 --backtrack=30 dev-perl/WWW-Mechanize:0
emerge -vD1 --backtrack=30 dev-perl/gnome2-canvas:0
emerge -vD1 --backtrack=30 dev-perl/gnome2-vfs-perl:0
emerge -vD1 --backtrack=30 dev-perl/IO-String:0
emerge -vD1 --backtrack=30 dev-perl/HTML-Tagset:0
emerge -vD1 --backtrack=30 dev-perl/Carp-Clan:0
emerge -vD1 --backtrack=30 dev-perl/Pod-Spell:0
emerge -vD1 --backtrack=30 dev-perl/Sane:0
emerge -vD1 --backtrack=30 dev-perl/TermReadKey:0
emerge -vD1 --backtrack=30 dev-perl/HTTP-Date:0
emerge -vD1 --backtrack=30 dev-perl/Encode-Locale:0
emerge -vD1 --backtrack=30 dev-perl/Event-RPC:0
emerge -vD1 --backtrack=30 dev-perl/File-HomeDir:0
emerge -vD1 --backtrack=30 dev-perl/Bit-Vector:0
emerge -vD1 --backtrack=30 dev-perl/gnome2-wnck:0
emerge -vD1 --backtrack=30 dev-perl/File-Copy-Recursive:0
emerge -vD1 --backtrack=30 dev-perl/Text-Unidecode:0
emerge -vD1 --backtrack=30 dev-perl/Unicode-EastAsianWidth:0
emerge -vD1 --backtrack=30 dev-perl/extutils-pkgconfig:0
emerge -vD1 --backtrack=30 dev-perl/Clone:0
emerge -vD1 --backtrack=30 dev-perl/Event-ExecFlow:0
emerge -vD1 --backtrack=30 dev-perl/B-Keywords:0
emerge -vD1 --backtrack=30 dev-perl/PDF-API2:0
emerge -vD1 --backtrack=30 dev-perl/HTTP-Negotiate:0
emerge -vD1 --backtrack=30 dev-perl/HTML-Form:0
emerge -vD1 --backtrack=30 dev-perl/extutils-depends:0
emerge -vD1 --backtrack=30 dev-perl/PlRPC:0
emerge -vD1 --backtrack=30 dev-perl/libwww-perl:0
emerge -vD1 --backtrack=30 dev-perl/gtk2-perl:0
emerge -vD1 --backtrack=30 dev-perl/File-MimeInfo:0
emerge -vD1 --backtrack=30 dev-perl/Font-TTF:0
emerge -vD1 --backtrack=30 dev-perl/libintl-perl:0
emerge -vD1 --backtrack=30 dev-perl/List-MoreUtils:0
emerge -vD1 --backtrack=30 dev-perl/Log-Log4perl:0
emerge -vD1 --backtrack=30 dev-perl/XML-DOM:0
emerge -vD1 --backtrack=30 dev-perl/HTML-Parser:0
emerge -vD1 --backtrack=30 dev-perl/Try-Tiny:0
emerge -vD1 --backtrack=30 dev-perl/XML-Twig:0
emerge -vD1 --backtrack=30 dev-perl/Gtk2-Ex-Simple-List:0
emerge -vD1 --backtrack=30 dev-perl/LWP-MediaTypes:0
emerge -vD1 --backtrack=30 dev-perl/LWP-Protocol-https:0
emerge -vD1 --backtrack=30 dev-perl/XML-Simple:0
emerge -vD1 --backtrack=30 dev-perl/Pango:0
emerge -vD1 --backtrack=30 dev-perl/set-scalar:0
emerge -vD1 --backtrack=30 dev-perl/Gtk2-Unique:0
emerge -vD1 --backtrack=30 dev-perl/Params-Util:0
emerge -vD1 --backtrack=30 dev-perl/Net-Daemon:0
emerge -vD1 --backtrack=30 dev-perl/GSSAPI:0
emerge -vD1 --backtrack=30 dev-perl/XML-NamespaceSupport:0
emerge -vD1 --backtrack=30 dev-perl/PPI:0
emerge -vD1 --backtrack=30 dev-perl/Proc-ProcessTable:0
emerge -vD1 --backtrack=30 dev-perl/String-Format:0
emerge -vD1 --backtrack=30 dev-perl/Date-Calc:0
emerge -vD1 --backtrack=30 dev-perl/XML-Parser:0
emerge -vD1 --backtrack=30 dev-perl/Email-Address:0
emerge -vD1 --backtrack=30 dev-perl/Class-Data-Inheritable:0
emerge -vD1 --backtrack=30 dev-perl/Email-Simple:0
emerge -vD1 --backtrack=30 dev-perl/JSON:0
emerge -vD1 --backtrack=30 dev-perl/gnome2-perl:0
emerge -vD1 --backtrack=30 dev-perl/XML-SAX-Base:0
emerge -vD1 --backtrack=30 dev-perl/Net-SMTP-SSL:0
emerge -vD1 --backtrack=30 dev-perl/Gtk2-ImageView:0
emerge -vD1 --backtrack=30 dev-perl/IO-HTML:0
emerge -vD1 --backtrack=30 dev-perl/WWW-RobotRules:0
emerge -vD1 --backtrack=30 dev-perl/Digest-HMAC:0
emerge -vD1 --backtrack=30 dev-perl/HTTP-Cookies:0
emerge -vD1 --backtrack=30 dev-perl/DBI:0
emerge -vD1 --backtrack=30 dev-perl/URI:0
emerge -vD1 --backtrack=30 dev-perl/Text-Iconv:0
emerge -vD1 --backtrack=30 dev-perl/gtk2-ex-formfactory:0
emerge -vD1 --backtrack=30 dev-perl/Email-Date-Format:0
emerge -vD1 --backtrack=30 dev-perl/libxml-perl:0
emerge -vD1 --backtrack=30 dev-perl/XML-SAX-Writer:0
emerge -vD1 --backtrack=30 dev-perl/XML-Filter-BufferText:0
emerge -vD1 --backtrack=30 dev-perl/Number-Compare:0
emerge -vD1 --backtrack=30 dev-perl/XML-RegExp:0
emerge -vD1 --backtrack=30 dev-perl/Email-LocalDelivery:0
emerge -vD1 --backtrack=30 dev-perl/config-general:0
emerge -vD1 --backtrack=30 dev-perl/HTTP-Daemon:0
emerge -vD1 --backtrack=30 dev-perl/File-Listing:0
emerge -vD1 --backtrack=30 dev-perl/Devel-StackTrace:0
emerge -vD1 --backtrack=30 dev-perl/Set-IntSpan:0
emerge -vD1 --backtrack=30 dev-perl/Cairo:0
emerge -vD1 --backtrack=30 dev-perl/Email-FolderType:0
emerge -vD1 --backtrack=30 dev-perl/XML-Handler-YAWriter:0
emerge -vD1 --backtrack=30 dev-perl/Archive-Zip:0
emerge -vD1 --backtrack=30 dev-perl/Net-DBus:0
emerge -vD1 --backtrack=30 dev-perl/DBD-mysql:0
emerge -vD1 --backtrack=30 dev-perl/AnyEvent:0
emerge -vD1 --backtrack=30 dev-perl/perltidy:0
emerge -vD1 --backtrack=30 dev-perl/Locale-gettext:0
emerge -vD1 --backtrack=30 dev-perl/Sort-Naturally:0
emerge -vD1 --backtrack=30 dev-perl/Net-HTTP:0
emerge -vD1 --backtrack=30 dev-perl/Perl-Critic:0
emerge -vD1 --backtrack=30 media-gfx/gscan2pdf:0
emerge -vD1 --backtrack=30 media-libs/exiftool:0
emerge -vD1 --backtrack=30 perl-core/CPAN-Meta-Requirements:0
emerge -vD1 --backtrack=30 virtual/perl-CPAN-Meta-Requirements:0
emerge -vD1 --backtrack=30 perl-core/IPC-Cmd:0
emerge -vD1 --backtrack=30 virtual/perl-IPC-Cmd:0
emerge -vD1 --backtrack=30 perl-core/Storable:0
emerge -vD1 --backtrack=30 virtual/perl-Storable:0
emerge -vD1 --backtrack=30 perl-core/File-Spec:0
emerge -vD1 --backtrack=30 virtual/perl-File-Spec:0
emerge -vD1 --backtrack=30 perl-core/CPAN-Meta:0
emerge -vD1 --backtrack=30 virtual/perl-CPAN-Meta:0
emerge -vD1 --backtrack=30 perl-core/Getopt-Long:0
emerge -vD1 --backtrack=30 virtual/perl-Getopt-Long:0
emerge -vD1 --backtrack=30 perl-core/Locale-Maketext-Simple:0
emerge -vD1 --backtrack=30 virtual/perl-Locale-Maketext-Simple:0
emerge -vD1 --backtrack=30 perl-core/ExtUtils-Manifest:0
emerge -vD1 --backtrack=30 virtual/perl-ExtUtils-Manifest:0
emerge -vD1 --backtrack=30 perl-core/Pod-Simple:0
emerge -vD1 --backtrack=30 virtual/perl-Pod-Simple:0
emerge -vD1 --backtrack=30 perl-core/CPAN-Meta-YAML:0
emerge -vD1 --backtrack=30 virtual/perl-CPAN-Meta-YAML:0
emerge -vD1 --backtrack=30 perl-core/Encode:0
emerge -vD1 --backtrack=30 virtual/perl-Encode:0
emerge -vD1 --backtrack=30 perl-core/Compress-Raw-Bzip2:0
emerge -vD1 --backtrack=30 virtual/perl-Compress-Raw-Bzip2:0
emerge -vD1 --backtrack=30 perl-core/Module-Load:0
emerge -vD1 --backtrack=30 virtual/perl-Module-Load:0
emerge -vD1 --backtrack=30 perl-core/Archive-Tar:0
emerge -vD1 --backtrack=30 virtual/perl-Archive-Tar:0
emerge -vD1 --backtrack=30 perl-core/Scalar-List-Utils:0
emerge -vD1 --backtrack=30 virtual/perl-Scalar-List-Utils:0
emerge -vD1 --backtrack=30 perl-core/ExtUtils-CBuilder:0
emerge -vD1 --backtrack=30 virtual/perl-ExtUtils-CBuilder:0
emerge -vD1 --backtrack=30 perl-core/Parse-CPAN-Meta:0
emerge -vD1 --backtrack=30 virtual/perl-Parse-CPAN-Meta:0
emerge -vD1 --backtrack=30 perl-core/version:0
emerge -vD1 --backtrack=30 virtual/perl-version:0
emerge -vD1 --backtrack=30 perl-core/Digest-SHA:0
emerge -vD1 --backtrack=30 virtual/perl-Digest-SHA:0
emerge -vD1 --backtrack=30 perl-core/Module-Load-Conditional:0
emerge -vD1 --backtrack=30 virtual/perl-Module-Load-Conditional:0
emerge -vD1 --backtrack=30 perl-core/Compress-Raw-Zlib:0
emerge -vD1 --backtrack=30 virtual/perl-Compress-Raw-Zlib:0
emerge -vD1 --backtrack=30 perl-core/ExtUtils-Install:0
emerge -vD1 --backtrack=30 virtual/perl-ExtUtils-Install:0
emerge -vD1 --backtrack=30 perl-core/IO:0
emerge -vD1 --backtrack=30 virtual/perl-IO:0
emerge -vD1 --backtrack=30 perl-core/Time-Local:0
emerge -vD1 --backtrack=30 virtual/perl-Time-Local:0
emerge -vD1 --backtrack=30 perl-core/Module-CoreList:0
emerge -vD1 --backtrack=30 virtual/perl-Module-CoreList:0
emerge -vD1 --backtrack=30 perl-core/Digest-MD5:0
emerge -vD1 --backtrack=30 virtual/perl-Digest-MD5:0
emerge -vD1 --backtrack=30 perl-core/JSON-PP:0
emerge -vD1 --backtrack=30 virtual/perl-JSON-PP:0
emerge -vD1 --backtrack=30 perl-core/ExtUtils-ParseXS:0
emerge -vD1 --backtrack=30 virtual/perl-ExtUtils-ParseXS:0
emerge -vD1 --backtrack=30 perl-core/File-Temp:0
emerge -vD1 --backtrack=30 virtual/perl-File-Temp:0
emerge -vD1 --backtrack=30 perl-core/Params-Check:0
emerge -vD1 --backtrack=30 virtual/perl-Params-Check:0
emerge -vD1 --backtrack=30 perl-core/Module-Metadata:0
emerge -vD1 --backtrack=30 virtual/perl-Module-Metadata:0
emerge -vD1 --backtrack=30 perl-core/Sys-Syslog:0
emerge -vD1 --backtrack=30 virtual/perl-Sys-Syslog:0
emerge -vD1 --backtrack=30 perl-core/IO-Compress:0
emerge -vD1 --backtrack=30 virtual/perl-IO-Compress:0
emerge -vD1 --backtrack=30 perl-core/Test-Harness:0
emerge -vD1 --backtrack=30 virtual/perl-Test-Harness:0

That’s all there is to it. :-)

Work-around if 64-bit Google Earth crashes in Gentoo Linux

Google Earth 5.2.1.1588 was the last version of Google Earth for Linux that worked on my main laptop running 64-bit Gentoo Linux. Even the Panoramio photos were displayed (a common complaint amongst users of Google Earth for Linux). But every subsequent version crashed when I launched it. The latest version, 7.1.2.2041, is no exception:

$ googleearth
[0403/012031:ERROR:net_util.cc(2195)] Not implemented reached in bool net::HaveOnlyLoopbackAddresses()
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:WARNING:backend_impl.cc(1875)] Destroying invalid entry.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
[0403/012033:ERROR:nss_ocsp.cc(581)] No URLRequestContext for OCSP handler.
Google Earth has caught signal 11.



We apologize for the inconvenience, but Google Earth has crashed.
This is a bug in the program, and should never happen under normal
circumstances. A bug report and debugging data have been written
to this text file:

/home/fitzcarraldo/.googleearth/crashlogs/crashlog-533ca953.txt

Please include this file if you submit a bug report to Google.

Now, the Google Earth installation package bundles the libraries it needs, so they are used instead of the ‘native’ libraries installed on your machine. A Linux user going by the moniker amirpli worked out how to enable Google Earth for Linux to use the native Qt libraries rather than the Qt libraries bundled with Google Earth, and posted instructions for a number of distributions (see, for example, Comment 9 in Gentoo Bugzilla Bug Report No. 490066). However, even if I apply amirpli‘s fix, Google Earth on my main laptop crashed with almost the same error message as above. Looking through the crash log file that Google Earth generates, I see the following line, which makes me suspect that Google Earth cannot work with the closed-source AMD ATI Catalyst driver (a.k.a. FGLRX):

./libbase.so(_ZN5earth15GfxCardInfoUnix25GetGraphicsCardMemoryInMBERi+0xe)[0x7f011b3e654e]

I noticed a few posts by users of other distributions in various forums saying that they had installed the 32-bit version of Google Earth in their 64-bit (multilib) installations, so I decided to try that in Gentoo. I hacked the ebuild of version 7.1.2.2041 to force it to install the 32-bit version of Google Earth on my 64-bit multilib installation, and installed it via a local overlay.

The hacked ebuild has the following changes from the stock 7.1.2.2041 ebuild:

a) Replace:

SRC_URI="x86? ( http://dl.google.com/dl/earth/client/current/google-earth-stable_current_i386.deb
                       -> GoogleEarthLinux-${PV}_i386.deb )
       amd64? ( http://dl.google.com/dl/earth/client/current/google-earth-stable_current_amd64.deb
                       -> GoogleEarthLinux-${PV}_amd64.deb )"

with:

SRC_URI="http://dl.google.com/dl/earth/client/current/google-earth-stable_current_i386.deb
                       -> GoogleEarthLinux-${PV}_i386.deb"


b) Replace:

unpack_deb GoogleEarthLinux-${PV}_$(usex amd64 "amd64" "i386").deb

with:

unpack_deb GoogleEarthLinux-${PV}_i386.deb


c) Replace:

patchelf --set-interpreter /lib/ld-linux$(usex amd64 "-x86-64" "").so.2 ${PN}-bin || die "patchelf failed"

with:

patchelf --set-interpreter /lib/ld-linux.so.2 ${PN}-bin || die "patchelf failed"


If you have not used a local overlay before, it is not difficult — just follow the steps given below.

1. If you have not done it before, tell Portage the location of the local overlay:

# echo 'PORTDIR_OVERLAY="${PORTDIR_OVERLAY} /usr/local/portage/"' >> /etc/make.conf

2. If you have not done it before, give your local overlay a name:

# mkdir /usr/local/portage/profiles
# echo "local_overlay" > /usr/local/portage/profiles/repo_name

3. Create the directories for the local overlay’s Google Earth ebuild and its associated files:

# mkdir -p /usr/local/portage/sci-geosciences/googleearth/files

4. Uninstall the non-functioning 64-bit version of Google Earth that you installed from the Portage main tree:

# emerge -C googleearth

5. Copy the main tree’s ebuild and associated files to the local overlay and edit the ebuild as per the changes I listed above:

# cp /usr/portage/sci-geosciences/googleearth/googleearth-7.1.2.2041.ebuild /usr/local/portage/sci-geosciences/googleearth/
# cp /usr/portage/sci-geosciences/googleearth/files/* /usr/local/portage/sci-geosciences/googleearth/files/
# cd /usr/local/portage/sci-geosciences/googleearth/
# nano googleearth-7.1.2.2041.ebuild

6. Create the manifest for the ebuild and associated files:

# ebuild googleearth-7.1.2.2041.ebuild manifest

7. Finally, install the package:

# emerge googleearth::local_overlay

The 32-bit version of Google Earth works fine in my 64-bit multilib installation, although the Panoramio photos are not displayed, but then Linux users are used to that :-/. Come on Google, you can do better than this!

Installing the Windows version of Google Earth in WINE

Some Gentoo Linux users have reported that, although the native Linux release of Google Earth crashes, they can run the Windows version successfully under WINE. However, those users have also reported that the Windows installer for Google Earth did not work under WINE and so they copied the C:\Program Files\Google\Google Earth\ directory from a Windows PC to the virtual C:\ drive in their .wine directory (it would be ‘Program Files (x86)‘ in a 64-bit Windows installation, as Google Earth is a 32-bit application).

Now, if you download the Windows Google Earth installer from the Google Web site, what you get is a file GoogleEarthWin.exe that is 534.6 KiB in size (the size may vary depending on the release). However, you can instead download the Offline Installer using the following URL:

http://dl.google.com/earth/client/advanced/current/GoogleEarthWin.exe

and then you get a file GoogleEarthWin.exe that is 24.3 MiB in size (the size will vary depending on the release), which does run in WINE and does install the Windows version of Google Earth in WINE.

So, you might like to try that if you cannot run Google Earth in Linux but you have WINE installed. However, note that you will be wasting your time if the native Linux version of Google Earth crashes because of its incompatibility with the closed-source ATI or NVIDIA video driver. For example, Google Earth 7.1.2.2041 for Linux crashes on my main laptop using the 14.3_beta version of ati-drivers (AMD ATI Catalyst driver, a.k.a. FGLRX).

Anyway, if you want to install the Windows release of Google Earth under WINE here’s how to do it in a Konsole/Terminal window:

$ cd
$ export WINEPREFIX=$HOME/.wine-googleearth
$ export WINEARCH="win32"
$ winecfg
$ cd ./.wine-googleearth/drive_c/
$ wget http://dl.google.com/earth/client/advanced/current/GoogleEarthWin.exe
$ wine GoogleEarthWin.exe

And, to run it later:

$ env WINEPREFIX="/home/fitzcarraldo/.wine-googleearth" WINEARCH="win32" wine C:\\windows\\command\\start.exe /Unix /home/fitzcarraldo/.wine-googleearth/dosdevices/c:/users/fitzcarraldo/Start\ Menu/Programs/Google\ Earth/Google\ Earth.lnk

(Of course replace “fitzcarraldo” with your user name.)

But, as I wrote above, if the native Linux version of Google Earth crashes due to its incompatibility with the closed-source video driver (ATI or NVIDIA), it is highly unlikely the native Windows version will work under WINE.

Bypassing a corporate Web filter when using the command line

or ‘How to bypass a corporate Web filter and download YouTube videos via the command line’

One of the offices where I work uses a Web filter to block access to certain sites, such as YouTube. However, sometimes it is necessary to view blocked Web sites for work purposes. For example, these days a lot of companies or individuals post product reviews on YouTube that are useful for work purposes. In such cases I have used Tor to access the blocked sites in a Web browser such as Firefox, Chrome, Konqueror etc. See my post How to install and use Tor for anonymous browsing or to access country-restricted content from another country for details of how to set up and use Tor with a Web browser.

But sometimes I need to access blocked Web sites from the command line. For example, today I needed to download a YouTube video for work purposes, and I wanted to use youtube-dl to do it. The solution was simple…

First I launched vidalia and polipo as explained in the above-mentioned post on Tor, then I launched another Konsole/Terminal window and entered the commands shown below:

$ # First find out what resolutions are available for the video I want to download:
$ youtube-dl -F https://www.youtube.com/watch?v=T3Rr4CUoTSQ
Setting language
T3Rr4CUoTSQ: Downloading webpage
T3Rr4CUoTSQ: Downloading video info webpage
T3Rr4CUoTSQ: Extracting video information
[info] Available formats for T3Rr4CUoTSQ:
format code extension resolution note
140 m4a audio only DASH audio , audio@128k (worst)
160 mp4 192p DASH video
133 mp4 240p DASH video
134 mp4 360p DASH video
135 mp4 480p DASH video
136 mp4 720p DASH video
17 3gp 176x144
36 3gp 320x240
5 flv 400x240
43 webm 640x360
18 mp4 640x360
22 mp4 1280x720 (best)
$ # Now try to download the video at the resolution I want:
$ youtube-dl -f 22 -o Clevo_W230ST_overview.flv https://www.youtube.com/watch?v=T3Rr4CUoTSQ
Setting language
T3Rr4CUoTSQ: Downloading webpage
T3Rr4CUoTSQ: Downloading video info webpage
T3Rr4CUoTSQ: Extracting video information
ERROR: unable to download video data: HTTP Error 403: Forbidden

As you can see above, the corporate Web filter blocked youtube-dl from downloading the video.

So I informed the shell session about the local HTTP proxy (polipo) running on my laptop, by assigning and exporting the environment variable http_proxy using the following syntax:

export http_proxy=http://server-ip:port/

which in my case meant the following (refer to my article on Tor):

$ export http_proxy=http://127.0.0.1:8123/

and then I was able to download the video from YouTube despite the corporate Web filter:

$ youtube-dl -f 22 -o Clevo_W230ST_overview.flv https://www.youtube.com/watch?v=T3Rr4CUoTSQ
Setting language
T3Rr4CUoTSQ: Downloading webpage
T3Rr4CUoTSQ: Downloading video info webpage
T3Rr4CUoTSQ: Extracting video information
[download] Destination: Clevo_W230ST_overview.flv
[download] 100% of 100.23MiB in 05:50
$

Useful Reference: How To Use Proxy Server To Access Internet at Shell Prompt With http_proxy Variable

Can Linux cope with 24 Hours of Happy?

I enjoyed Pharrell Williams’ feel-good songs in ‘Despicable Me‘ and its sequel, ‘Despicable Me 2‘. ‘Happy‘, a very catchy ditty he wrote for the sequel, also features in the World’s first 24-hour-long music video, ‘24 Hours of Happy‘, shot in and around Los Angeles and released on 21 November last year. The song is played a total of 360 times over the duration of the video, each 4-minute take featuring a different person or persons dancing (improvised) along streets, in petrol stations, through Union Station, in a church, around a school, in a moving school bus, around a supermarket, in a bowling alley, and so on. Each 4-minute performance was filmed in one take using Steadicam, and the location at the end of each take segues into the next take. You see the sun rise; you see the bright sunlight of the morning and the warm sunlight of the afternoon; you see the sun set; you see the twinkling city lights at night. The concept is simple yet brilliant.

Clips from some of the takes were used to create the 4-minute official music video for ‘Happy’, so you can watch that on YouTube to get a flavour of the takes, although it does not do justice to the full video.

Williams appears in a different take every hour on the hour, and a few other takes have celebrity cameos, but the vast majority of the participants are unknown extras of all ages, races, shapes, sizes and looks. To quote Williams talking to the Los Angeles Times: “We wanted all humanity in there, not just the model-types you might expect.” Some are good dancers, others not so good. But they all have one thing in common: they’re having fun, so they look good. The joy is infectious, and I found myself watching far longer than I would have expected, having to return to the site again and again. Half the fun is watching the bystanders.

When you open the ’24 Hours of Happy’ site, the take that was in progress at the current time of day starts playing from the beginning. However, you can drag the pointer around the clock dial and watch any take from the 24-hour period. There are also buttons you can click on to jump between takes or to jump to each take featuring Williams. The yellow on-screen controls can be made to disappear by not moving the mouse pointer for 5 seconds.

Still from 24 Hours of Happy, showing on-screen controls

Still from 24 Hours of Happy, showing on-screen controls

The Web site is well-designed and fun to use, so I was not surprised it was voted ‘Site of the Month‘ and ‘Site of the Year Users’ Choice‘ by AWWWARDS, and voted ‘Site of the Month‘ and ‘Site of the Year‘ by TheFWA.

It’s impossible to list them all, but a few of my favourite takes are:

01:36  Very perky woman with ponytail.
05:28  Jogger who has to keep pulling his shorts up!
08:24  Woman on roller skates.
09:52  Very cute little girl.
09:56  Woman with some groovy moves.
10:40  Woman in Union Station. Some of the bystanders are particularly amusing.
11:16  Man with cast on foot.
11:20  Boy with an Afro.
11:36  Three groovy old ladies.
11:44  Chubby guy with style.
12:36  Woman with some groovy moves.
13:32  Dancing couple in pink.
14:20  Two cool guys in dinner jackets inside and outside Union Station.
15:00  Pharrell Williams in a church with a gospel choir.
19:04  Woman with a lizard puppet. The lizard does the lip-synching!
19:36  Guy on stilts.
23:40  Woman with LED hula hoop (love it!).

If you want to start viewing a take made at a specific time of day, you can append the time to the URL, like so:

http://24hoursofhappy.com/09h53am

Obviously I think ’24 Hours of Happy’ is fabulous, but why am I discussing it in a blog predominantly about Linux? Because Firefox 27.0.1 (32-bit) running in Windows 8.1 (64-bit) on my new Acer Aspire XC-600 micro-tower PC (dual-core Intel Pentium G2030 @ 3 GHz & 3 MB cache, 4 GB DDR3 RAM) handles ’24 Hours of Happy’ at 720p with ease, but the story is very different on my main laptop running 64-bit Gentoo Linux with KDE (quad-core Intel Core i7 720QM @ 933 MHz & 6 MB cache, 4 GB DDR3 RAM). Both machines are on my home network, connected to the Internet via high-bandwidth broadband (FTTC).

On my laptop, the latest available versions of Firefox (27.0) and Opera (12.16_p1860-r1) for Gentoo, both 64-bit, do not even complete loading the ’24 Hours of Happy’ site: the black progress bar at the bottom of the home page stops about 7/8th of the way across the page and the KDE Network Monitor widget shows there is no network activity. Clearing Firefox’s Web content cache or increasing the cache’s size to 1 GB make no difference. Konqueror 4.12.2 (configured to use the WebKit browser engine rather than the KHTML engine) loads the site and plays it quite well at 720p to start with, but eventually video becomes choppy and I notice a lot of spawned kio_http processes. The KDE Network Monitor widget shows a continuous 3600 Kib/s data stream, which does not stop when I exit Konqueror. Numerous kio_http processes are spawned and remain after I exit Konqueror, and the 3600 KiB/s activity on the network only ceases when I kill all the kio_http processes. The number of spawned kio_http processes increases if I drag the pointer around the clock to select different takes, and the page just displays ‘LOADING’ ad infinitum if I do this several times. To be fair, if I do this a lot in Firefox running in Windows 8.1, I can get Firefox to stall too. I thought I’d try a lightweight browser and installed NetSurf (3.0-r1), but that couldn’t even render the title on the home page, let alone begin to load the video.

So, does ’24 Hours of Happy’ play nicely in your Linux installation? If it does, what hardware, distribution, desktop environment, browser and quality (360p, 480p, 720p or 1080p) are you using?

KDE Connect – Link your Android device to your KDE desktop

KDE Connect app icon on my Samsung Galaxy Note II

KDE Connect app icon on my Samsung Galaxy Note II

KDE Connect is a nice tool that links your Android phone or tablet seamlessly via WiFi to KDE on your PC (the latter can be connected via WiFi or cable to the network). It allows your KDE desktop to receive notifications, files and media player commands from your Android device. The available KDE Connect plug-ins are:

Battery report
Periodically report battery status

Clipboard sync
Share the clipboard content

Multimedia remote controls
Control audio/video from your phone
(pause; first track; previous track; next track; last track; change volume)

Notification sync
Access your notification from other devices

Ping
Send and receive pings

Telephony notifier
Send notifications from SMS and calls

You will need to install the Android KDE Connect application on your Android device, and the Linux KDE Connect application on your PC.

Install the KDE Connect app on your Android device from the Google Play Store. You will then see the KDE Connect icon on the apps screen of your Android device.

For Gentoo users an ebuild for KDE Connect is available in the Gentoo KDE team’s testing overlay, so here are the instructions on how to install KDE Connect on your PC from there.

Firstly, mask the KDE overlay so that none of the packages in it interferes with the KDE software you installed from the main Portage tree:

# echo "*/*::kde" >> /etc/portage/package.mask

Then unmask the KDE Connect package in the KDE overlay:

# echo "kde-misc/kdeconnect" >> /etc/portage/package.unmask

N.B. If /etc/portage/package.mask is a directory rather than a file (either is possible) in your installation, and if /etc/portage/package.unmask is a directory rather than a file (either is possible) in your installation, use the following commands instead of the above two commands:

# echo "*/*::kde" > /etc/portage/package.mask/kde_overlay
# echo "kde-misc/kdeconnect" > /etc/portage/package.unmask/kdeconnect

Now add the KDE overlay and merge the package:

# layman -a kde
# emerge kdeconnect

If a firewall is running on your PC, you will need to configure it to allow tcp and udp traffic via a specific range of ports (1714 to 1764). I have UFW running on my main laptop, so in my case I used the following commands:

# ufw allow proto tcp to any port 1714:1764
# ufw allow proto udp to any port 1714:1764

The rules should look like this:

# ufw status verbose | grep 1714
1714:1764/tcp ALLOW IN Anywhere
1714:1764/udp ALLOW IN Anywhere
1714:1764/tcp ALLOW IN Anywhere (v6)
1714:1764/udp ALLOW IN Anywhere (v6)

If you have the KConfig Module kcm_ufw installed on your PC then you can instead use System Settings > Firewall to add the UFW rules via the KDE GUI.

By the way, to check which KConfig modules are installed on your PC you can use the following command under your user account:

$ kcmshell4 --list

Using KDE Connect is not difficult, so I will leave you to play with it. Obviously make sure WiFi is enabled on your Android device, and that it and your PC are connected to the same network. Tap on the KDE Connect icon on your Android device to launch the app, and you should see your PC’s name listed under CONNECTED DEVICES. Tap on the PC name and you should see the following screen:

KDE Connect screen

KDE Connect screen

If you tap on ‘Send ping’, the KDE Notification widget on the KDE System Tray should pop up a notification.

You can see what KDE Connect plug-ins are available, and select/deselect them:

KDE Connect plugins

KDE Connect plugins

KDE Connect also enables you to use your Android device as a remote control for media players running on your PC. When you launch a media player in KDE its name will appear in a list of selectable players in KDE Connect, and the name of the track currently playing will also be displayed:

KDE Connect - Remote control

KDE Connect - Remote control

When you select a file on your Android device and tap the Share icon, KDE Connect will be one of the options displayed on the ‘Share via’ menu. This is a handy way to send files from your Android device to your PC. The KDE Notification widget on your PC will notify you when the file has been transferred to ~/Desktop/ on your PC:

KDE on your PC notifies you when a file has been sent via KDE Connect

KDE on your PC notifies you a file has been sent via KDE Connect

You should also get notifications on your KDE desktop when someone phones or sends you an SMS.

Kudos and many thanks to the people responsible for KDE Connect. KDE is already a superb desktop environment, and with the addition of KDE Connect it is better still.

Gentoo Linux

I suspect Gentoo Linux is a complete mystery to most Linux users, let alone everyone else. It is a Linux distribution I would never recommend to a newcomer to Linux or to someone not used to the command line, as it requires a certain amount of experience and knowledge when something goes wrong. This is especially true for Gentoo’s Testing Branch. Take upgrading Gentoo Testing on my main laptop today as a good example of what I mean…

Unlike most Linux distributions, Gentoo is a ‘source distribution’, meaning that the software is compiled and installed on your machine from source code downloaded by Gentoo build scripts called ‘ebuilds’, not installed pre-compiled as in a ‘binary distribution’. Furthermore, Gentoo is a ‘rolling distribution’, meaning that you do not periodically install a new release of the operating system, you install it once via the Internet using a lengthy set of commands, and thereafter ‘roll’ it forward by upgrading the installed packages (one, or several at a time) ad infinitum as new versions are released. The upgrading of all installed packages on your machine to their latest versions is called a ‘world update’. For Gentoo Stable you would expect this to be straightforward and trouble-free, and usually it is. But problems are to be expected in the case of Gentoo Testing.

To illustrate the level of detail a user of Gentoo Testing may need to go into, I’ll talk you through what happened to me today when I upgraded the world on my main laptop. I will not explain precisely what each command does; I just want to illustrate the sort of troubleshooting a Gentoo user has to perform from time to time.

I kicked off the world upgrade:

# emerge --sync
# layman --sync-all
# emerge --update --verbose --deep --newuse --keep-going world

This upgraded several installed packages but the last package in the list to be upgraded, version 6.7.0 of a suite of tools named mkvtoolnix, failed to compile. The error message displayed in the terminal window left me none the wiser, so I surfed over to the Gentoo Bugzilla Web site and searched for bug reports on mkvtoolnix. I found Gentoo Bug No. 499332 (‘media-video/mkvtoolnix-6.7.0 should DEPEND on >=dev-lang/ruby-1.9′).

From the title of the bug report I knew I should have a look at the ebuild (an ‘ebuild’ is a script file that Gentoo uses to compile and install a package), so I searched for it on my laptop using the command:

# locate mkvtoolnix | grep 6.7.0.ebuild

which found the file /usr/portage/media-video/mkvtoolnix/mkvtoolnix-6.7.0.ebuild, so I used the text editor nano to look at the ebuild’s code and changed ‘dev-lang/ruby’ to ‘>=dev-lang/ruby-1.9′, then recreated the package manifest:

# cd /usr/portage/media-video/mkvtoolnix
# ebuild mkvtoolnix-6.7.0.ebuild manifest

Gentoo is 'slotted' (i.e. different versions of the same package can be installed), so I checked the currently selected version of Ruby:

# eselect ruby list
Available Ruby profiles:
[1] ruby18 (with Rubygems) *
[2] ruby19 (with Rubygems)
[3] ruby20 (with Rubygems)
[4] ruby21 (with Rubygems)

and changed it to be Ruby version 1.9 as follows:

# eselect ruby set 2
# eselect ruby list
Available Ruby profiles:
[1] ruby18 (with Rubygems)
[2] ruby19 (with Rubygems) *
[3] ruby20 (with Rubygems)
[4] ruby21 (with Rubygems)

Then I tried again to install the mkvtoolnix-6.7.0 package:

# emerge --oneshot --verbose mkvtoolnix

and this time it was built and installed without trouble.

Lastly, I used a Gentoo tool to check, and if necessary fix, dependencies:

# revdep-rebuild --ignore

The output from revdep-rebuild told me everything was fine, so revdep-rebuild did not need to rebuild any packages and I did not need to do anything further.

Actually, I probably could have skipped editing the mkvtoolnix ebuild and just selected Ruby 1.9 using the eselect tool before trying to re-install mkvtoolnix-6.7.0, but if mkvtoolnix depends on Ruby 1.9 or higher then the ebuild for Version 6.7.0 ought to be modified in any case.

If you have read down to here, perhaps now you can see why using Gentoo requires a fair amount of prior knowledge.

Fixing a problem with received video in Skype when using the AMD Catalyst (FGLRX) driver in Linux

Some users of Skype for Linux have reported that the bottom half of the received video image is corrupted in installations that use the closed-source video driver for ATI GPUs (the AMD Catalyst proprietary Linux driver, also known as the ‘FGLRX’ driver). One user described the lower half of the video image as “covered in small coloured squares like a chequer board”.

From what I have read in a few forums, it seems the problem does not occur when the open-source Radeon driver is used. My own experience corroborates that: I use the Radeon driver on one of my laptops, and received video in Skype is fine.

My main laptop has an AMD ATI Mobility Radeon HD 5650 GPU and I am using the Catalyst driver under Gentoo Linux. In this case there was a problem with received video in most Skype sessions. Either of the following effects usually occurred:

Snapshot 1 - Extract of received video image in Skype, showing an example of the corrupted image

Snapshot 1 - Extract of received video image in Skype, showing an example of the corrupted image

Snapshot 2 - Extract of received video image in Skype, showing another example of the corrupted image

Snapshot 2 - Extract of received video image in Skype, showing another example of the corrupted image

As shown in Snapshot 1, the lower half of the received video image was covered in a grid of thin green lines with areas tinged with purple, blue or green, whereas there was no grid of lines in the upper half of the image but some areas were tinged with red or blue.

As shown in Snapshot 2, the lower half of the received video image was covered in a grid of thin red lines, with a purple tinge in some areas, whereas there was no grid of lines in the upper half of the image, which looked reasonable but had some red-, green- or blue-tinged areas.

In all cases Skype’s thumbnail of my Webcam’s video image looked fine, and the person on the other end of the call said the video image received from me looked fine too.

Because of a bug in a previous version of the Catalyst driver a few years ago — see my blog posts Playing QuickTime videos in Firefox and Chromium + XVideo bug in AMD Catalyst 11.11 and 11.12 driver and AMD Catalyst for Linux driver 12.2 fixes the XVideo bug that crashed X.Org Server 1.11.x — I happen to know that Sykpe uses X11 overlays with the XVideo extension (xv), rather than using the OpenGL renderer (gl) or X11 with the SHM extension (x11). This made me wonder whether the use of XVideo with the Catalyst driver was causing the current problem. Unlike media players such as MPlayer and VLC, it is not possible to configure Skype to use gl or x11 instead of xv, so I thought it would not be possible to test whether the use of gl or x11 instead of xv would make a difference. Until, that is, I came upon a ‘trick’ posted by openSUSE user queequeg in 2009 during the period when an earlier version of the Catalyst driver had the aforementioned bug:

Skype Video Workaround for ATI

Anybody trying to make a video call with Skype and ATI fglrx drivers has had problems due to Skype using the “xv” video mode with the driver can’t handle. For anyone interested that is affected by this, there is a workaround:

1. Run the xvinfo command and look at the number of xv sessions available. Some cards have only 1, some have as many as 4. This is the number of xv occurances that the card can do at one time.
2. “Use up” all these xv sessions by opening videos in your favorite video player making sure to use xv for the video output. The videos can then be paused.
3. Once this (or they) are open, skype can be started and will default to X11 video and work properly with video calls.

I know this is a goofy way to get around this issue, but until fglrx can handle xv or skype allows an option to choose X11 for video render, I don’t know of any other way to do it.

(From what I hear, the 11.1 fglrx drivers can handle xv, but I haven’t confirmed this.)

So I tried his work-around. I had to launch four media players in order to use all available XVideo sessions. Lo and behold, when I launched Skype and made a video call the received video image was perfect. So it appeared that the Catalyst driver is not able to handle well the XVideo output from Skype. However, playing and pausing four videos every time I want to make a video call in Skype would hardly be practical, would it? And that is not the only downside: when I maximised a Firefox window during the Skype video call, my laptop spontaneously rebooted (I assume the X.Org server crashed).

I did also wonder whether just disabling compositing would solve the problem, so I disabled KWin Desktop Effects, but that didn’t make any difference.

I had also read in several forums that enabling or disabling the TexturedVideo and/or VideoOverlay options in the xorg.conf file have an effect on the video image produced by the Catalyst driver, but I could not find a post mentioning the use of either of those options to fix the specific problem I was seeing. So I decided not to pursue the xorg.conf route.

In my searches of the Web I came across a post somewhere that mentioned using GTK+ UVC Viewer (guvcview) to adjust video properties and improve video in Skype. I thought guvcview was only for adjusting the video image from a Webcam connected to my machine, i.e. adjusting the outgoing video image, and would not have any effect on received video. Nevertheless, I decided to install and launch guvcview to see if I could adjust both incoming and outgoing video properties. To my surprise, guvcview appeared to have fixed the problem with the received video. These are the steps I followed:

  1. I launched Skype and started a video call. The received video image had a grid of thin red lines and purple/green/blue tinting (similar to Snapshot 2).
  2. I Installed guvcview using the package manager.
  3. I launched guvcview in a Konsole (terminal) window. After guvcview created the file /home/fitzcarraldo/.config/guvcview/video0 and checked various video and audio settings it exited because my Webcam was being used by Skype (‘libv4l2: error setting pixformat: Device or resource busy‘).
  4. I clicked on the Webcam icon in the Skype call window, to turn my Webcam off.
  5. I launched guvcview again. The lower half of the received video image in Skype changed from a grid of thin red lines to a continuous green-coloured band, and the upper half of the image now looked reasonable but still had some red- or blue-tinged areas (see Snapshot 3 below).
  6. Snapshot 3 - Extract of received video image in Skype after I launched guvcview again

    Snapshot 3 - Extract of received video image in Skype after I launched guvcview again

  7. On the ‘Image Controls’ tab in the ‘GUVCViewer Controls’ window I changed the video frequency from 60 Hz to 50 Hz then back to 60 Hz again. I was just tinkering, and I believe this had no bearing on the outcome.
  8. I clicked on the ‘Quit’ button in the guvcview window to terminate the application.
  9. I clicked on the Webcam icon in the Skype call window to turn on again the Webcam, and the received Skype video image changed to a perfect image (see Snapshot 4 below).
  10. Snapshot 4 - Extract of received video image in Skype after I turned on again my Webcam in Skype

    Snapshot 4 - Extract of received video image in Skype after I turned on again my Webcam in Skype

It appears that guvcview had an effect on the received video image in Skype, although, if it did, I do not understand how. To check if the fix was permanent I ended the Skype video call, signed out of Skype and quit the application, rebooted and made a new Skype video call. The received video image in Skype was again perfect. I even deleted the guvcview configuration file and repeated this check, just in case the configuration file was somehow being used even though I had not launched guvcview, but the received video in yet another Skype video call was still perfect. I also clicked on the Webcam icon in the Skype call window several times during each call in order to turn my Webcam off and on several times; the received video image of the other person remained perfect.

So there you have it: when using an AMD ATI GPU and the Catalyst driver, it seems that guvcview can be used — at least in my case — to eliminate the type of image corruption in received Skype video shown in Snapshots 1 and 2. So, if you are also using the AMD Catalyst for Linux driver and are experiencing a similar problem, try guvcview. It might just do the trick.

Split an A4 PDF file into two A5 PDF files

This week I scanned a couple of receipts in order to submit them to a client with an expenses claim. The two receipts were physically small enough to both fit on an A4 page, so I lay them both on the bed of a scanner and produced a PDF file with the two receipts on one A4 page. The resulting scan looked rather like the sketch in Figure 1. However, a couple of days later I remembered that the client wanted copies of receipts to be submitted individually, but the office scanner had stopped working and so I needed to split the original PDF file into two PDF files containing images rather like the sketches in Figures 2 and 3.

Figure 1 - original A4 image

Figure 1 - original A4 image

Figure 2 - A5 bottom half of original A4 image

Figure 2 - A5 bottom half of original A4 image

Figure 3 - A5 top half of original A4 image

Figure 3 - A5 top half of original A4 image

I was surprised to find little information on the Web about how to do such a thing. I did come across three applications that looked like they probably could do the job: jPdf Tweak, BRISS and krop. jPdf Tweak is in the Portage main tree (app-text/jpdftweak). BRISS isn’t. The krop Web page does have a link to an ebuild which could be downloaded and installed via a local overlay. I did have a brief play with jPdf Tweak and it looks powerful, but I did not find it particularly intuitive and I would need to study the manual in detail. Anyway, I thought I would try a command line approach for the fun of it.

Searching the Web I came across a site with a Perl script that looked promising: Split (crop) double page PDFs in two posted by someone called iblis (to whom I’m grateful). It uses a Perl module PDF:API2 which does exist in the Portage main tree (dev-perl/PDF-API2) and which I already had installed. I modified the last couple of lines of the script very slightly, so it now looks like this:

#!/usr/bin/env perl
use strict; use warnings;
use PDF::API2;
     
my $filename = shift || 'test.pdf';
my $oldpdf = PDF::API2->open($filename);
my $newpdf = PDF::API2->new;
     
for my $page_nb (1..$oldpdf->pages) {
my ($page, @cropdata);
     
$page = $newpdf->importpage($oldpdf, $page_nb);
@cropdata = $page->get_mediabox;
$cropdata[2] /= 2;
$page->cropbox(@cropdata);
$page->trimbox(@cropdata);
$page->mediabox(@cropdata);
     
$page = $newpdf->importpage($oldpdf, $page_nb);
@cropdata = $page->get_mediabox;
$cropdata[0] = $cropdata[2] / 2;
$page->cropbox(@cropdata);
$page->trimbox(@cropdata);
$page->mediabox(@cropdata);
}
     
(my $newfilename = $filename) =~ s/(.*)\.(\w+)$/$1.split.$2/;
$newpdf->saveas($newfilename);
     
__END__

I saved it with the file name split_pdf_A4_to_A5.pl and made it executable:

$ chmod +x split_pdf_A4_to_A5.pl

Then I used the following procedure to split the original PDF file:

1. I used the excellent command line utility pdftk (the package app-text/pdftk in Gentoo), which I had already installed, to rotate the A4 page clockwise and save it in a file named rotated.pdf:

$ pdftk original.pdf rotate 1-1right output rotated.pdf

Now the A4 page looked similar to the sketch in Figure 4.

Figure 4 - original A4 image, rotated clockwise by 90 degrees

Figure 4 - original A4 image, rotated clockwise by 90 degrees

2. I used the Perl script to split the A4 page into two A5 pages within one PDF file:

$ ./split_pdf_A4_to_A5.pl rotated.pdf

The above command created a file rotated.split.pdf containing two A5 pages.

3. Finally, I split the two-page PDF file into two separate single-page files:

$ pdftk rotated.split.pdf burst

which left me with two A5 PDF files named page_0001.pdf and page_0002.pdf similar to the sketches in Figures 2 and 3 above.

Mission accomplished. :-)

‘Server not found’ by browser at launch

I haven’t had any significant Linux problems or new requirements in the last few months, hence no new posts here. My last real problem was back in June 2013 when I rolled my Gentoo installation to latest using Portage and found that, whenever I launched Firefox, it displayed the ‘Server not found’ page and I had to click ‘Try Again’, and then Firefox displayed the expected Web site. From then onwards, Firefox would work as expected until I exited the application. Thunderbird was also unable to access e-mail servers on the first attempt after it was launched. The same thing happened in Sabayon Linux when I rolled to latest using Entropy a couple of days later. Anyway, here is how I fixed the problem in both distributions.

First I used Wireshark to see what was going on, and it transpired that Gentoo (and Sabayon) was sending an IPv4 request followed quickly by an IPv6 request, but the reply to the IPv6 request was being received first and was a ‘server not found’ message since my ISP does not support IPv6 and my router apparently does not handle IPv6 requests correctly. Gentoo (and Sabayon) then used an IPv4 address when I clicked ‘Try Again’ in the browser window, and thereafter Firefox always dispayed the expected Web sites.

I should point out that IPv6 is enabled in the kernels I use and I’ve never before had to disable IPv6 in Firefox (or system-wide) on the affected laptops. So why the change in functionality, I wonder?

With Wireshark capturing packets, when I launched Firefox I was seeing a server failure message indicating “AAAA” (IPv6) instead of “A” (IPv4). To stop this happening I could have chosen any one of the three following solutions:

1. I could have used about:config in Firefox (and Config Editor in Thunderbird) to change the value of network.dns.disableIPv6 to true instead of false.

2. I could have disabled IPv6 system-wide by editing /etc/modprobe.d/aliases.conf and uncommenting the line “alias net-pf-10 off“.

3. I could have forced the getaddrinfo() function in glibc to make the IPv4 and IPv6 requests sequentially rather than in parallel.

Just for the fun of it I chose the third option on a couple of my laptops, and, as they use NetworkManager, this is how I did it:

fitzcarraldo@aspire5536 ~ $ su
Password:
aspire5536 fitzcarraldo # cat /etc/resolv.conf
# Generated by resolvconf
domain home
nameserver 192.168.1.254
aspire5536 fitzcarraldo # cd /etc/NetworkManager/dispatcher.d/
aspire5536 dispatcher.d # touch 06-dhclientoptions
aspire5536 dispatcher.d # nano 06-dhclientoptions
aspire5536 dispatcher.d # cat 06-dhclientoptions
#!/bin/bash
echo "options single-request" >> /etc/resolv.conf
aspire5536 dispatcher.d # chmod +x /etc/NetworkManager/dispatcher.d/06-dhclientoptions
aspire5536 dispatcher.d # # Now I disconnect then reconnect to the network
aspire5536 dispatcher.d # cat /etc/resolv.conf
# Generated by resolvconf
domain home
nameserver 192.168.1.254
options single-request
aspire5536 dispatcher.d #

As you can see above, I added a two-line Bash script 06-dhclientoptions in the directory /etc/NetworkManager/dispatcher.d/ that appends the line “options single-request” (without the quotes) to the contents of the file /etc/resolv.conf. The addition of the line “options single-request” in resolve.conf causes the getaddrinfo() function in glibc to make the IPv4 and IPv6 requests sequentially rather than in parallel. With this change, Firefox and Thunderbird no longer have a problem accessing the Internet the first time they are launched.

From “man 5 resolv.conf” under “options”:

single-request (since glibc 2.10)
sets RES_SNGLKUP in _res.options. By default, glibc performs IPv4 and IPv6 lookups in parallel since version 2.9. Some appliance DNS servers cannot handle these queries properly and make the requests time out. This option disables the behavior and makes glibc perform the IPv6 and IPv4 requests sequentially (at the cost of some slowdown of the resolving process).

single-request-reopen (since glibc 2.9)
The resolver uses the same socket for the A and AAAA requests. Some hardware mistakenly sends back only one reply. When that happens the client system will sit and wait for the second reply. Turning this option on changes this behavior so that if two requests from the same port are not handled correctly it will close the socket and open a new one before sending the second request.

I had to use NetworkManagerDispatcher to add the line “options single-request” to /etc/resolv.conf because NetworkManager overwrites /etc/resolv.conf if you edit it manually.

UPDATE (February 4, 2014): As I have recently seen the line “options single-request” occurring more than once in the file /etc/resolv.conf I now recommend /etc/NetworkManager/dispatcher.d/06-dhclientoptions consists of the following:

#!/bin/bash
if grep -q "options single-request" /etc/resolv.conf; then
    exit
else
    echo "options single-request" >> /etc/resolv.conf
fi

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