Commands using cat (514)

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Mount a VMware virtual disk (.vmdk) file on a Linux box
Assumes XP/2000/2003. For Server 2008+ try offset=105,906,176 You can find this number in the System Information utility under Partition Starting Offset. UEFI based boxes you want partition 2 since the first is just the boot files (and FAT). This works with (storage side) snapshots which is handy for single file restores on NFS mounted VMware systems

Open Remote Desktop (RDP) from command line having a custom screen size
This example uses xfreerdp, which builds upon the development of rdesktop. This example usage will also send you the remote machine's sound.

List processes sorted by CPU usage

faster version of ls *
I know its not much but is very useful in time consuming scripts (cron, rc.d, etc).

list block devices
Shows all block devices in a tree with descruptions of what they are.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Record a screencast and convert it to an mpeg
Grab X11 input and create an MPEG at 25 fps with the resolution 800x600

Lists unambigously names of all xml elements used in files in current directory
This set of commands was very convenient for me when I was preparing some xml files for typesetting a book. I wanted to check what styles I had to prepare but coudn't remember all tags that I used. This one saved me from error-prone browsing of all my files. It should be also useful if one tries to process xml files with xsl, when using own xml application.

Recurse through directories easily
This is a simple case of recursing through all directories, adding the '.bak' extension to every file. Of course, the 'cp $file $file.bak' could be any code you need to apply to your recursion, including tests, other functions, creating variables, doing math, etc. Simple and clean recursion.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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