utime.3

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 3 代码 · 共 117 行

.\" SCCSID: @(#)utime.3	2.1	3/10/87
.TH utime 3
.SH Name
utime \- set file times
.SH Syntax
.nf
.B #include <sys/types.h>
.B int utime (\fIpath, times\fP)
.B char *\fIpath\fP;
.B struct utimbuf *\fItimes\fP;
.fi
.SH Description
.NXR "utime function"
.NXR "file" "setting access time"
.NXR "file" "setting modification time"
The
.I path
points to a pathname naming a file.  The
.PN utime
function
sets the access and modification times
of the named file.
.PP
If
.I times
is NULL,
the access and modification times
of the file are set to the current time.
A process must be the owner of the file
or have write permission to use
.PN utime
in this manner.
.PP
If
.I times
is not NULL,
.I times
is interpreted as a pointer to a
.I utimbuf
structure and
the access and modification times
are set to the values contained in
the designated structure.  Only the
owner of the file or the super-user can use
.PN utime
this way.
.PP
The function
.PN utime
causes the time of the last file status 
change(st_ctime) to be updated with the current time.
.PP
The times in the following structure
are measured in seconds since 00:00:00
GMT\*S,
January 1, 1970.
.EX 0
struct  utimbuf  {
        time_t  actime;    /* access time */
        time_t  modtime;   /* modification time */
};
.EE
.SH Return Values
Upon successful completion, a value of zero (0) is returned.  
Otherwise, a value of \-1 is returned, and 
.I errno
is set to indicate the error.
.SH Diagnostics
The
.PN utime
function fails, if any of the following is true:
.TP 15
[EACCES]
Search permission is denied by a component of the
.I path
prefix.
.TP 15
[EACCES]
The effective user ID is not super-user, not the owner of the file,
.I times
is NULL, and write access is denied.
.TP 15
[EFAULT]
The
.I times
is not NULL and points outside the process's allocated address space.
.TP 15
[EFAULT]
The
.I path
points outside the process's allocated address space.
.TP 15
[ENOENT]
The named file does not exist or
.I path
points to an empty string and the environment defined is POSIX or SYSTEM_FIVE.
.TP 15
[ENOTDIR]
A component of the
.I path
prefix is not a directory.
.TP 15
[EPERM]
The effective user ID is not a super-user, not the owner of the file, and
.I times
is not NULL.
.TP 15
[EROFS]
The file system containing the file is mounted read-only.
.TP 15
[ETIMEDOUT]
A connect request or remote file operation failed, because the connected party
did not respond after a period of time determined by the communications
protocol.
.SH See Also
stat(2)