user_namespaces.7: Minor wording improvement

Mainly in preparation for the following patch on project IDs maps.
Add some words that will make the parallels between the rules for
updating uid_map and projid_map clearer.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

diff --git a/man7/user_namespaces.7 b/man7/user_namespaces.7
index 6af6c787adb258b1e1821fdd6b9dd751248e9b01..3bba32cb5612d22e17edd079317e52bc7b582fb8 100644 (file)
--- a/man7/user_namespaces.7
+++ b/man7/user_namespaces.7
@@ -518,7 +518,7 @@ files.
 The lines written to
 .IR uid_map
 .RI ( gid_map )
-must conform to the following rules:
+must conform to the following validity rules:
 .IP * 3
 The three fields must be valid numbers,
 and the last field must be greater than 0.
@@ -561,7 +561,7 @@ Writes that violate the above rules fail with the error
 In order for a process to write to the
 .I /proc/[pid]/uid_map
 .RI ( /proc/[pid]/gid_map )
-file, all of the following requirements must be met:
+file, all of the following permission requirements must be met:
 .IP 1. 3
 The writing process must have the
 .BR CAP_SETUID