diff --git a/lib/libc/sys/read.2 b/lib/libc/sys/read.2
index b3dfa925572..2e906b22960 100644
--- a/lib/libc/sys/read.2
+++ b/lib/libc/sys/read.2
@@ -215,7 +215,9 @@ The
 system call may also return the following errors:
 .Bl -tag -width Er
 .It Bq Er EINVAL
-The specified file offset is invalid, i.e. negative.
+The
+.Fa offset
+value was negative.
 .It Bq Er ESPIPE
 The file descriptor is associated with a pipe, socket, or FIFO.
 .El
diff --git a/lib/libc/sys/write.2 b/lib/libc/sys/write.2
index 55389c0a48f..19b5ce2dea3 100644
--- a/lib/libc/sys/write.2
+++ b/lib/libc/sys/write.2
@@ -231,7 +231,9 @@ The
 system call may also return the following errors:
 .Bl -tag -width Er
 .It Bq Er EINVAL
-The specified file offset is invalid, i.e. negative.
+The
+.Fa offset
+value was negative.
 .It Bq Er ESPIPE
 The file descriptor is associated with a pipe, socket, or FIFO.
 .El