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--- linux:dev1_3manage [2026/01/09 21:00] – created azman
+++ linux:dev1_3manage [2026/01/09 21:05] (current) – [List Installed Packages] azman
@@ Line 6: / Line 6: @@
 To automatically update system essentials, <code>$ apt install unattended-upgrades ; dpkg-reconfigure --priority=low unattended-upgrades</code>
+===== List Installed Packages =====
+  * Using ''apt'' tool <code>$ apt list --installed 2>/dev/null | grep installed</code>
+    * Note that apt will issue a warning when piping its output in shell. Hence, the need to redirect ''stderr'' to ''/dev/null''.
+    * We can further grep away the packages that were automatically installed.
+  * Using the basic ''dpkg'' tool <code>$ dpkg --get-selections | sed -n 's/^\([^\t]*\)\t.*$/\1/ p'</code>
+    * This version, however, only provides package name.
+    * To extract similar output from ''apt'' (assuming output was redirected into a file called ''temp.txt''), run <code>$ cat temp.txt | sed -n 's|^\(.*\)/.*$|\1| p'</code>