[strace] Add example of tracing file operations

pages/linux/strace.md

@@ -18,6 +18,10 @@
 
 `strace -p {{pid}} -T`
 
-- Start tracing a program by executing it:
+-- Start tracing a program by executing it:
 
 `strace {{program}}`
+
+- Start tracing file operations of a program:
+
+`strace -e trace=file {{program}}`