Hdi2u S13 - Revision history

Rf: Created page with "= Reading text files = * These are useful when you want to look at the contents of a file, but not edit it. * Among the most common of these commands are `cat`,
2017-04-19T22:34:45Z

Created page with "= Reading text files = * These are useful when you want to look at the contents of a file, but not edit it. * Among the most common of these commands are <code>cat</code>, <c..."

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= Reading text files =

* These are useful when you want to look at the contents of a file, but not edit it.
* Among the most common of these commands are <code>cat</code>, <code>more</code>, and <code>less</code>.

* <code>cat</code> simply prints out one or several files out.
* Useful for small files, but also for concatenating (which is where it got its name)
* <code>more</code> and <code>less</code> are pagers
* You can feed output to them via the pipe operator
* they have keybindings similar to the editor vi: <code>/</code>, <code>?</code>, <code>gg</code>. <code>G</code>.

== Exercises ==
* Move into the hdi2u_files directory.
* Read the file hsy14768.embl using the commands cat, more and less.
* Don’t forget that tab completion can save you typing effort.
cat hsy14768.embl
more hsy14768.embl
less hsy14768.embl

* Use the spacebar to scroll down
* Press q to quit.
* Use the spacebar to scroll down, b to go up a page, and the up and down arrow keys to move up and down the file line by line.
* Press the / key and search for the letters sequen in the file.
* Press the ? key and search for the letters gene in the file.
* Press the n key to search for other instances of gene in the file.