diff --git a/io_posix.cpp b/io_posix.cpp
index d15dbda3..1e0dbeb3 100644
--- a/io_posix.cpp
+++ b/io_posix.cpp
@@ -83,7 +83,7 @@ mapped_file::~mapped_file ()
 }
 
 
-//----------------------------------------------------------------------------
+//////////////////////////////////////////////////////////////////////////////
 size_t
 mapped_file::size (void) const
 {
diff --git a/posix/fd.cpp b/posix/fd.cpp
index 115bfd93..46a945f6 100644
--- a/posix/fd.cpp
+++ b/posix/fd.cpp
@@ -107,6 +107,14 @@ fd::stat (void) const
 }
 
 
+///////////////////////////////////////////////////////////////////////////////
+void
+fd::allocate (int mode, off_t offset, off_t len)
+{
+    error::try_call (fallocate, m_fd, mode, offset, len);
+}
+
+
 ///////////////////////////////////////////////////////////////////////////////
 void
 fd::close (void)
diff --git a/posix/fd.hpp b/posix/fd.hpp
index 1064b9b0..0babda96 100644
--- a/posix/fd.hpp
+++ b/posix/fd.hpp
@@ -57,6 +57,11 @@ namespace cruft::posix {
         struct ::stat stat (void) const;
 
 
+        ///////////////////////////////////////////////////////////////////////
+        /// A thin wrapper around `fallocate`
+        void allocate (int mode, off_t offset, off_t len);
+
+
         ///////////////////////////////////////////////////////////////////////
         void close (void);
         void reset (int);