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→INVESTIGATION 3: OTHER COMMANDS THAT USE REGULAR EXPRESSIONS
# We want to search for an option that can sort the file listing.<br>Type the following regular expression below and press '''ENTER''':<br><span style="color:blue;font-weight:bold;font-family:courier;">/sort</span><br><br>'''FYI:''' The '''grep''' and '''egrep''' linux commands contain the regular expressions within quotes,<br>but '''most''' other Linux commands specify regular expressions using forward slashes<br>(e.g. <span style="font-weight:bold;font-family:courier;">/regular expression</span> or <span style="font-weight:bold;font-family:courier;">/regular expression</span>).<br><br>
# Scroll throughout the man pages for the ls command to view matches for the pattern "'''sort'''"<br>(You can press '''SPACE''' or key combination '''alt-b''' to move forward and backwards one screen respectively).<br><br>
# Press the letter <span style="color:blue;font-weight:bold;font-family:courier;">q</span> to '''exit''' the ''man'' pages for '''ls'''.<br><br>#Let's use regular expressions with the '''more''' command.<br><br># Issue the following Linux command to download another data file called '''large-file.txt''':<br><span style="color:blue;font-weight:bold;font-family:courier;">wget <nowiki>https://ict.senecacollege.ca/~murray.saul/uli101/large-file.txt</nowiki></span><br><br># View the contents of the '''large-file.txt''' file using the '''more''' command and quickly view the contents of this file.<br><br>Issue the following linux command to view the contents of the '''textfile1.txt''' (downloaded in a previous section):<br><span style="color:blue;font-weight:bold;font-family:courier;">more textfile1.txt</span><br><br>
#We want to search for a pattern '''uli101''' within this text file.<br>Type the following regular expression and press ENTER:<br><span style="color:blue;font-weight:bold;font-family:courier;">/uli101</span><br><br>What did you notice?<br><br>
#Search for the next occurrence of the pattern '''uli101''' by '''re-typing'''<br>the following regular expression and pressing ENTER:<br><span style="color:blue;font-weight:bold;font-family:courier;">/uli101</span><br><br>you should now see the '''second occurrence''' of this pattern within the text file.<br><br>
