logsave: add page (#4486)

pages/linux/logsave.md

@@ -0,0 +1,20 @@
+# logsave
+
+> Save the output of a command in a logfile.
+> More information: <https://linux.die.net/man/8/logsave>.
+
+- Execute command with specified argument(s) and save its output to log file:
+
+`logsave {{path/to/logfile}} {{command}}`
+
+- Take input from standard input and save it in a log file:
+
+`logsave {{logfile}} -`
+
+- Append the output to a log file, instead of replacing its current contents:
+
+`logsave -a {{logfile}} {{command}}`
+
+- Show verbose output:
+
+`logsave -v {{logfile}} {{command}}`