diff --git a/functions/filesystem.xml b/functions/filesystem.xml
index 5fdca74258..36695124e2 100644
--- a/functions/filesystem.xml
+++ b/functions/filesystem.xml
@@ -1220,6 +1220,27 @@ fclose ($fd);
+
+
+ ftruncate
+
+ Truncate a file to a given length.
+
+
+
+ Description
+
+ int ftruncate
+ int fp
+ int size
+
+
+ Takes the filepointer, fp, and truncates the file to length, size.
+ This function returns true on success and false on failure.
+
+
+
+
fwrite