futimes(3) Library Functions Manual futimes(3)

futimes, lutimes - change file timestamps

Standard C library (libc, -lc)

#include <sys/time.h>
int futimes(int fd, const struct timeval tv[2]);
int lutimes(const char *filename, const struct timeval tv[2]);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

futimes(), lutimes():

    Since glibc 2.19:
        _DEFAULT_SOURCE
    glibc 2.19 and earlier:
        _BSD_SOURCE

futimes() changes the access and modification times of a file in the same way as utimes(2), with the difference that the file whose timestamps are to be changed is specified via a file descriptor, fd, rather than via a pathname.

lutimes() changes the access and modification times of a file in the same way as utimes(2), with the difference that if filename refers to a symbolic link, then the link is not dereferenced: instead, the timestamps of the symbolic link are changed.

On success, zero is returned. On error, -1 is returned, and errno is set to indicate the error.

Errors are as for utimes(2), with the following additions for futimes():

fd is not a valid file descriptor.
The /proc filesystem could not be accessed.

The following additional error may occur for lutimes():

The kernel does not support this call; Linux 2.6.22 or later is required.

For an explanation of the terms used in this section, see attributes(7).

Interface Attribute Value
futimes (), lutimes () Thread safety MT-Safe

Linux, BSD.

glibc 2.3.
glibc 2.6.

lutimes() is implemented using the utimensat(2) system call.

utime(2), utimensat(2), symlink(7)

2023-10-31 Linux man-pages 6.06