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--- linux_wiki:sed [2016/02/05 13:29]
billdozor [Remove Lines]
+++ linux_wiki:sed [2019/05/25 23:50] (current)
@@ Line 6: / Line 6: @@
 **Checklist**
-  * Linux distro with the 'sed' package installed
+  * Distro(s): Any
+  * Package: 'sed' package installed
 ----
-===== Insert Lines =====
+====== Print Lines ======
+Different ways to print specific lines.
+Print only line 5 pattern space<code bash>sed -n '5p' /etc/passwd</code>
+  * -n => silent; do not print the entire file
+Line 5, don't delete it<code bash>sed '5!d' /etc/passwd</code>
+  * !d => don't delete
+Print up to line 5, quit and delete the rest of the output<code bash>sed '5q;d' /etc/passwd</code>
+  * q => quit/stop processing more input
+  * d => delete the pattern space (removes all but line 5 from output)
+----
+====== Swap Patterns ======
+Edit files by swapping pattern spaces.
+  * Before<code bash>cat /etc/resolv.conf
+# Generated by NetworkManager
+search local
+nameserver 208.67.222.222
+nameserver 208.67.220.220</code>
+  * After<code bash>sed -i 's/208.67.222.222/8.8.8.8/g' /etc/resolv.conf
+# Generated by NetworkManager
+search local
+nameserver 8.8.8.8
+nameserver 208.67.220.220</code>
+    * -i => In-line editing
+    * s => swap
+    * g => global swap (swap every match, not just the first one)
+----
+====== Insert Lines ======
 Insert lines before a found matched pattern.
@@ Line 35: / Line 72: @@
 </code>
-==== Insert at first line ====
+===== Insert at first line =====
 Insert also works against line numbers.
@@ Line 54: / Line 91: @@
 ----
-===== Append Lines =====
+====== Append Lines ======
 Append lines after a found matched pattern.
@@ Line 80: / Line 117: @@
 ----
-===== Remove Lines =====
+====== Remove Lines ======
 Remove lines that match a pattern.