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Today, I follow this tutorial Skype Installation in order to install Skype on Fedora 16. In the instruction, the author says that:

touch /usr/bin/skype
chmod 755 /usr/bin/skype

Open /usr/bin/skype with text editor and add following content:
export SKYPE_HOME="/opt/skype"

I don't understand the way touch and chmod 755 work together? Not only in this tutorial but some other tutorials I came up with, I also see these two commands go together when installing programs in Linux.

Moreover, I don't know what this line means

export SKYPE_HOME="/opt/skype"

Please explain to me. Thanks in advance.

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Note: the /usr/bin/skype shell script you are creating also needs a command to actually start the skype application. The recipe at… also includes this line $SKYPE_HOME/skype --resources=$SKYPE_HOME $* – Brian Swift Apr 2 '12 at 16:34
@BrianSwift thank you, but only above commands make me confused – William Le Apr 3 '12 at 14:08
up vote 3 down vote accepted

touch /usr/bin/skype

This command will create the file /usr/bin/skype if it does not already exist. Read more about touch.

chmod 755 /usr/bin/skype

This command will change the mode of /usr/bin/skype. Read more about chmod.

  • 7 means the file owner can read, write, and execute the file.
  • 5 means members of the group that owns the file can read and execute the file.
  • The last 5 means anyone on the computer can read and execute the file.

export SKYPE_HOME="/opt/skype"

This command will create an environment variable named SKYPE_HOME. Read more about export.

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creates an new file with current date/time.

chmod 755

allow owner to read/write/execute file, everyone else - to read and execute (no write).

export SKYPE_HOME="/opt/skype"

creates an Environemental Variable called SKYPE_HOME for Skype's internal use.

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touch creates files, or updates an existing files time/date. It won't work for a directory that doesn't exist. – Rob Apr 2 '12 at 15:19
@Rob it's a file sorry – HackToHell Apr 2 '12 at 15:20
chmod 755 in this context means allow owner to read/write/execute file, everyone else - to read and execute (no write) – TimSparrow Apr 2 '12 at 16:29

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