Hdi2u S13

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, more, and less.

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

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.