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--- labs:unix_intermediate [2008/10/12 20:24] – admin
+++ labs:unix_intermediate [2024/09/05 17:21] (current) – [Intermediate Unix Commands] admin
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+====== Intermediate Unix Commands ======
+This page contains just a teaser of some helpful commands.  You should use ''man'' or search for more information about the commands, e.g., what arguments and flags you can use to customize the command.
+===== Permissions =====
+UNIX organizes permissions by user, group, and others.  There are three different permissions available: read, write, and execute
+''chmod'' is the command to change permissions
+==== Groups ====
+To change the group associated with a file, use ''chgrp''
+===== Finding Content: grep =====
+Gnu Regular Expression Print (''grep'') is a helpful tool to search for text within files, using--you guessed it--regular expressions!  Regular expressions can be quite simple.
+Example: I want to find all the names that start with "Sara" in a file of names
+  grep Sara names.txt
+===== Finding Files: find =====
+You can find files with various characteristics using the ''find'' command.  It will look in the directory specified and all of its subdirectories.  You can then apply a command to those found files.
+Examples:
+Find all of the files with the .txt extension in the current directory and its subdirectories
+  find . -name "*.txt"
+Find all of the files in my home directory (and its subdirectories) that have no data in them (have 0 Bytes of data)
+  find ~ -size 0
+View all of the information (e.g., last modified date) of all of the files in my home directory (and its subdirectories) that have no data in them
+  find ~ -size 0 -exec ls -l {} \;
+===== Finding Differences Between Files: diff =====
+===== Beginning of Files: head =====
+Usage:
+  head <filename>
+shows the first few lines of a file.  You can use a flag to change how many lines are displayed
+===== End of Files: tail =====
+===== Viewing Services Listening on a Port =====
+  lsof -i :<port>
+e.g.,
+  lsof -i :8080