This is files/t_utimes.c, an example to accompany the book, The Linux Programming Interface.

This file is not printed in the book; it is a supplementary file for Chapter 15.

The source code file is copyright 2022, Michael Kerrisk, and is licensed under the GNU General Public License, version 3.

In the listing below, the names of Linux system calls and C library functions are hyperlinked to manual pages from the Linux man-pages project, and the names of functions implemented in the book are hyperlinked to the implementations of those functions.


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Function list (Bold in this list means a function is not static)

/* t_utimes.c

   Demonstrate the use of utimes(): set the last modification time on a file to
   be the same as the last access time, but tweak the microsecond components of
   the two timestamps.

   Usage: t_utimes file

   See also t_utime.c.
#include <sys/stat.h>
#include <sys/time.h>
#include "tlpi_hdr.h"
main(int argc, char *argv[])
    if (argc != 2 || strcmp(argv[1], "--help") == 0)
        usageErr("%s file\n", argv[0]);

    struct stat sb;
    if (stat(argv[1], &sb) == -1)       /* Retrieve current file times */

    struct timeval tv[2];
    tv[0].tv_sec = sb.st_atime;         /* Leave atime seconds unchanged */
    tv[0].tv_usec = 223344;             /* Change microseconds for atime */
    tv[1].tv_sec = sb.st_atime;         /* mtime seconds == atime seconds */
    tv[1].tv_usec = 667788;             /* mtime microseconds */

    if (utimes(argv[1], tv) == -1)



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