man3/futimes.3

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  25 .TH FUTIMES 3 2017-09-15 "Linux" "Linux Programmer's Manual"
  26 .SH NAME
  27 futimes, lutimes \- change file timestamps
  28 .SH SYNOPSIS
  29 .nf
  30 .B #include <sys/time.h>
  31 .PP
  32 .BI "int futimes(int " fd ", const struct timeval " tv [2]);
  33 .PP
  34 .BI "int lutimes(const char *" filename ", const struct timeval " tv [2]);
  35 .fi
  36 .PP
  37 .in -4n
  38 Feature Test Macro Requirements for glibc (see
  39 .BR feature_test_macros (7)):
  40 .in
  41 .PP
  42 .BR futimes (),
  43 .BR lutimes ():
  44     Since glibc 2.19:
  45         _DEFAULT_SOURCE
  46     Glibc 2.19 and earlier:
  47         _BSD_SOURCE
  48 .SH DESCRIPTION
  49 .BR futimes ()
  50 changes the access and modification times of a file in the same way as
  51 .BR utimes (2),
  52 with the difference that the file whose timestamps are to be changed
  53 is specified via a file descriptor,
  54 .IR fd ,
  55 rather than via a pathname.
  56 .PP
  57 .BR lutimes ()
  58 changes the access and modification times of a file in the same way as
  59 .BR utimes (2),
  60 with the difference that if
  61 .I filename
  62 refers to a symbolic link, then the link is not dereferenced:
  63 instead, the timestamps of the symbolic link are changed.
  64 .SH RETURN VALUE
  65 On success, zero is returned.
  66 On error, \-1 is returned, and
  67 .I errno
  68 is set appropriately.
  69 .SH ERRORS
  70 Errors are as for
  71 .BR utimes (2),
  72 with the following additions for
  73 .BR futimes ():
  74 .TP
  75 .B EBADF
  76 .I fd
  77 is not a valid file descriptor.
  78 .TP
  79 .B ENOSYS
  80 The
  81 .I /proc
  82 filesystem could not be accessed.
  83 .PP
  84 The following additional error may occur for
  85 .BR lutimes ():
  86 .TP
  87 .B ENOSYS
  88 The kernel does not support this call; Linux 2.6.22 or later is required.
  89 .SH VERSIONS
  90 .BR futimes ()
  91 is available since glibc 2.3.
  92 .BR lutimes ()
  93 is available since glibc 2.6, and is implemented using the
  94 .BR utimensat (2)
  95 system call, which is supported since kernel 2.6.22.
  96 .SH ATTRIBUTES
  97 For an explanation of the terms used in this section, see
  98 .BR attributes (7).
  99 .TS
 100 allbox;
 101 lbw20 lb lb
 102 l l l.
 103 Interface       Attribute       Value
 104 T{
 105 .BR futimes (),
 106 .BR lutimes ()
 107 T}      Thread safety   MT-Safe
 108 .TE
 109 .SH CONFORMING TO
 110 These functions are not specified in any standard.
 111 Other than Linux, they are available only on the BSDs.
 112 .SH SEE ALSO
 113 .BR utime (2),
 114 .BR utimensat (2),
 115 .BR symlink (7)