lock screen shortcut centos 6

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Firefox 31+ crashes in centos 6.4/6+

After updating firefox on Centos 6.4 it started showing the following error and would not start firefox.

$ firefox\n
/usr/lib64/firefox/firefox: symbol lookup error: /usr/lib64/firefox/libxul.so: undefined symbol: gdk_window_get_visual

The issue was resolved after installing

$ sudo yum list gdk-pixbuf2

Still if you get the following error:

/usr/lib64/firefox/firefox: symbol lookup error: /usr/lib64/libgdk-x11-2.0.so.0: undefined symbol: _XGetRequest

Then update gtk and libX11, in my case gtk was already updated to the latest version so, just updated the libX11 and it worked

$ sudo yum update libX11

R snippet to remove quotes from a data frame

as.data.frame(sapply(dataFrameName, function(x) gsub("\"", "", x)))