ucred.9: crsetgroups_and_egid(): Clarify differences with crsetgroups()

MFC after:      5 days
MFC to:         stable/15
Sponsored by:   The FreeBSD Foundation
Differential Revision:  https://reviews.freebsd.org/D52288

1 files changed, 13 insertions, 15 deletions

diff --git a/share/man/man9/ucred.9 b/share/man/man9/ucred.9
index 38759bddb5b0..453df386ff18 100644
--- a/share/man/man9/ucred.9
+++ b/share/man/man9/ucred.9
@@ -24,7 +24,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 .\" DAMAGE.
 .\"
-.Dd July 29, 2025
+.Dd August 29, 2025
 .Dt UCRED 9
 .Os
 .Sh NAME
@@ -113,28 +113,26 @@ The actual copying is performed by
 .Pp
 The
 .Fn crsetgroups
-and
-.Fn crsetgroups_and_egid
-functions set the
+function sets the
 .Va cr_groups
 and
 .Va cr_ngroups
-variables and allocates space as needed.
-They also truncate the group list to the current maximum number of
-groups.
-No other mechanism should be used to modify the
-.Va cr_groups
-array.
-Note that
+variables representing the supplementary groups, allocating space as needed.
+It also truncates the group list to the current maximum number of groups.
+The
 .Fn crsetgroups_and_egid
-will interpret the first element of
+function is similar, but interprets separately the first group of
 .Va groups
-as the new effective GID and the rest of the array as the supplementary groups,
-and
+as the effective GID to set, only setting the subsequent groups as supplementary
+ones.
+It will use
 .Va default_egid
-will be used as the new effective GID only if
+as the new effective GID if
 .Va groups
 is empty.
+No other mechanism should be used to modify the
+.Va cr_groups
+array.
 .Pp
 The
 .Fn cru2x