From 6eaec6b167977270e3ef60469481483b38fb0e7f Mon Sep 17 00:00:00 2001 From: Michael Kerrisk Date: Tue, 17 Jun 2014 17:20:35 +0200 Subject: [PATCH] adjtimex.2: Document ADJ_OFFSET_SS_READ Signed-off-by: Michael Kerrisk --- man2/adjtimex.2 | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) diff --git a/man2/adjtimex.2 b/man2/adjtimex.2 index e927bf788..6d1d2e054 100644 --- a/man2/adjtimex.2 +++ b/man2/adjtimex.2 @@ -148,8 +148,25 @@ Old-fashioned .BR adjtime (): (gradually) adjust time by value specified in .IR buf.offset . +.TP +.BR ADJ_OFFSET_SS_READ " (functional since Linux 2.6.28)" +.\" In user space, ADJ_OFFSET_SS_READ is 0xa001 +.\" In kernel space there is ADJ_OFFSET_READONLY (0x2000) anded with +.\" ADJ_ADJTIME (0x8000) and ADJ_OFFSET_SINGLESHOT (0x0001) to give 0xa001) +Return (in +.BR buf.offset ) +the remaining amount of time to be adjusted after an earlier +.BR ADJ_OFFSET_SINGLESHOT +operation. +This feature was added in Linux 2.6.24, +.\" commit 52bfb36050c8529d9031d2c2513b281a360922ec +but did not work correctly +.\" commit 916c7a855174e3b53d182b97a26b2e27a29726a1 +until Linux 2.6.28. .PP -Ordinary users are restricted to a zero value for +Ordinary users are restricted to a value of either 0 or +.B ADJ_OFFSET_SS_READ +for .IR modes . Only the superuser may set any parameters. @@ -228,7 +245,9 @@ is the system timer interrupt frequency. .TP .B EPERM .I buf.modes -is nonzero and the caller does not have sufficient privilege. +is neither 0 nor +.BR ADJ_OFFSET_SS_READ , +and the caller does not have sufficient privilege. Under Linux the .B CAP_SYS_TIME capability is required.