diff --git a/pages/common/greater-than.md b/pages/common/greater-than.md
index 4d345e7322..1c0552559d 100644
--- a/pages/common/greater-than.md
+++ b/pages/common/greater-than.md
@@ -26,3 +26,11 @@
 - Redirect `stderr` to `stdout` for piping them together:
 
 `{{command1}} 2>&1 | {{command2}}`
+
+- Open a persistent file descriptor:
+
+`exec {{3}}>{{path/to/file}}`
+
+- Write to a custom file descriptor:
+
+`{{echo text}} >&{{3}}`
diff --git a/pages/common/less-than.md b/pages/common/less-than.md
index a844f33cea..09c070a47d 100644
--- a/pages/common/less-than.md
+++ b/pages/common/less-than.md
@@ -30,3 +30,7 @@
 - Pass command output to a program as a file descriptor:
 
 `diff <({{command1}}) <({{command2}})`
+
+- Open a persistent file descriptor:
+
+`exec {{3}}<{{path/to/file}}`