From: Omar Sandoval <osandov@xxxxxx> Signed-off-by: Omar Sandoval <osandov@xxxxxx> --- man2/utimensat.2 | 38 +++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) diff --git a/man2/utimensat.2 b/man2/utimensat.2 index d61b43e96..3b7c62181 100644 --- a/man2/utimensat.2 +++ b/man2/utimensat.2 @@ -211,7 +211,7 @@ is ignored. .PP The .I flags -field is a bit mask that may be 0, or include the following constant, +field is a bit mask that may be 0, or include the following constants, defined in .IR <fcntl.h> : .TP @@ -220,6 +220,36 @@ If .I pathname specifies a symbolic link, then update the timestamps of the link, rather than the file to which it refers. +.TP +.B AT_UTIME_BTIME +Also update the file's "creation time" (\fIbtime\fP). If +.I times +is not NULL, then its length must be at least 3, and +.IR times [2] +specifies the new creation time. The +.I tv_nsec +field may be +.BR UTIME_NOW +or +.BR UTIME_OMIT ; +this has the same meaning as for the first two timestamps. +If +.I times +is NULL, then the creation time is set to the current time. +.IP +Not all filesystems store the file creation time; if a filesystem does not, an +error is returned. At least the following filesystems store the creation time: +.RS +.IP * 3 +Btrfs +.IP * +ext4, if the filesystem was created with an inode size of at least 256 +.IP * +F2FS, if the filesystem was created with the inode_crtime feature +.IP * +XFS, if the filesystem was created with the v5 format (i.e., with CRCs enabled) +.HP +Support for this flag was added in Linux 5.2. .SH RETURN VALUE On success, .BR utimensat () @@ -359,6 +389,12 @@ or, one of the prefix components of .I pathname is not a directory. .TP +.B EOPNOTSUPP +.I flags +contains +.BR AT_UTIME_BTIME +but the filesystem does not store the file creation time. +.TP .B EPERM The caller attempted to change one or both timestamps to a value other than the current time, -- 2.20.1
