using stat to provide timestamp for touch












10















Am trying to OCR some documents insitu (from a linux command line on a windows share). The process of OCRing is find and I have muddled through using the find command to pipe the files through the loop correctly.



However I need to preserve the original timestamp for modified. I am currently trying to use stat and touch as below:



#!/bin/bash
OLDIFS=$IFS

IFS=$(echo -en "nb")

for f in `find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`
do
ORIGTS=`stat -c "%Y" $f`
sudo /opt/ABBYYOCR9/abbyyocr9 -rl English -pi -if $f -f PDFA -paemImageOnText -pafpr original -of $f
touch -t $ORIGTS $f

done

IFS=$OLDIFS


Of course the touch command fails. running the commands separately I notice "stat -c" is something along the lines of this:



1334758696



which is like no date I know. I feel as if I am close but cannot work out how to convert the date I have in to a touch friendly version. Is it some form of seconds from something?










share|improve this question























  • Aside: your use of IFS seems unusual. Did you really want to split on backspace (b)? See unix.stackexchange.com/questions/9496/… for some tips.

    – Mikel
    Apr 18 '12 at 19:31
















10















Am trying to OCR some documents insitu (from a linux command line on a windows share). The process of OCRing is find and I have muddled through using the find command to pipe the files through the loop correctly.



However I need to preserve the original timestamp for modified. I am currently trying to use stat and touch as below:



#!/bin/bash
OLDIFS=$IFS

IFS=$(echo -en "nb")

for f in `find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`
do
ORIGTS=`stat -c "%Y" $f`
sudo /opt/ABBYYOCR9/abbyyocr9 -rl English -pi -if $f -f PDFA -paemImageOnText -pafpr original -of $f
touch -t $ORIGTS $f

done

IFS=$OLDIFS


Of course the touch command fails. running the commands separately I notice "stat -c" is something along the lines of this:



1334758696



which is like no date I know. I feel as if I am close but cannot work out how to convert the date I have in to a touch friendly version. Is it some form of seconds from something?










share|improve this question























  • Aside: your use of IFS seems unusual. Did you really want to split on backspace (b)? See unix.stackexchange.com/questions/9496/… for some tips.

    – Mikel
    Apr 18 '12 at 19:31














10












10








10


2






Am trying to OCR some documents insitu (from a linux command line on a windows share). The process of OCRing is find and I have muddled through using the find command to pipe the files through the loop correctly.



However I need to preserve the original timestamp for modified. I am currently trying to use stat and touch as below:



#!/bin/bash
OLDIFS=$IFS

IFS=$(echo -en "nb")

for f in `find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`
do
ORIGTS=`stat -c "%Y" $f`
sudo /opt/ABBYYOCR9/abbyyocr9 -rl English -pi -if $f -f PDFA -paemImageOnText -pafpr original -of $f
touch -t $ORIGTS $f

done

IFS=$OLDIFS


Of course the touch command fails. running the commands separately I notice "stat -c" is something along the lines of this:



1334758696



which is like no date I know. I feel as if I am close but cannot work out how to convert the date I have in to a touch friendly version. Is it some form of seconds from something?










share|improve this question














Am trying to OCR some documents insitu (from a linux command line on a windows share). The process of OCRing is find and I have muddled through using the find command to pipe the files through the loop correctly.



However I need to preserve the original timestamp for modified. I am currently trying to use stat and touch as below:



#!/bin/bash
OLDIFS=$IFS

IFS=$(echo -en "nb")

for f in `find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`
do
ORIGTS=`stat -c "%Y" $f`
sudo /opt/ABBYYOCR9/abbyyocr9 -rl English -pi -if $f -f PDFA -paemImageOnText -pafpr original -of $f
touch -t $ORIGTS $f

done

IFS=$OLDIFS


Of course the touch command fails. running the commands separately I notice "stat -c" is something along the lines of this:



1334758696



which is like no date I know. I feel as if I am close but cannot work out how to convert the date I have in to a touch friendly version. Is it some form of seconds from something?







bash scripting stat






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Apr 18 '12 at 15:05









Tim AlexanderTim Alexander

16317




16317













  • Aside: your use of IFS seems unusual. Did you really want to split on backspace (b)? See unix.stackexchange.com/questions/9496/… for some tips.

    – Mikel
    Apr 18 '12 at 19:31



















  • Aside: your use of IFS seems unusual. Did you really want to split on backspace (b)? See unix.stackexchange.com/questions/9496/… for some tips.

    – Mikel
    Apr 18 '12 at 19:31

















Aside: your use of IFS seems unusual. Did you really want to split on backspace (b)? See unix.stackexchange.com/questions/9496/… for some tips.

– Mikel
Apr 18 '12 at 19:31





Aside: your use of IFS seems unusual. Did you really want to split on backspace (b)? See unix.stackexchange.com/questions/9496/… for some tips.

– Mikel
Apr 18 '12 at 19:31










5 Answers
5






active

oldest

votes


















14














stat's output is a Unix timestamp, also called seconds since the Epoch.



All GNU coreutils that accept a date allow you to put a timestamp instead by prefixing the timestamp with an @.



So try this



touch -d @$ORIGTS $f


See coreutils - Seconds since the epoch






share|improve this answer


























  • ah that explains a lot of timestamps i have seen in linux now! Thanks alot

    – Tim Alexander
    Apr 18 '12 at 15:38



















8














touch can use a file's timestamp using the -r option. You might want to output to a different file (I assume below that -if is input file and -of is output file)



for f in ...; do
sudo /opt/ABBYYOCR9/abbyyocr9 ... -if $f ... -of $f.new
touch -r $f $f.new
mv $f.new $f
done





share|improve this answer
























  • +1 for avoiding stat.

    – l0b0
    Apr 18 '12 at 15:39



















3















IFS=$(echo -en "nb")




Since you're assuming a shell with echo -e, and you have bash in your shebang line anyway, you can use IFS=$'nb'. Making backspace a separator is rather weird. You don't need IFS for what you're doing anyway.




OLDIFS=$IFS


IFS=$OLDIFS




Note that this restores the old value of IFS only if IFS was initially set. If IFS was initially unset, this sets IFS to the empty string, which is completely different. In ksh, bash or zsh, if you need to set IFS temporarily, you can write your code in a function and make IFS local to this function. In other shells, you need to be careful about the unset case.




`find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`




Never use command substitution on the output of find.




  • This splits the output at the characters in $IFS. If you set IFS to a newline, then this splits the output at newlines, but you still can't handle file names containing newlines.

  • Not only is the result of command substitution split into words, but then each word is used as a glob pattern. If you files called A[12].pdf, A1.pdf and A2.pdf, you'll end up with A1.pdf A2.pdf A1.pdf A2.pdf. You can turn globbing off with set -f (and back on with set +f), but here (like most of the time) the right way is not to use command substitution.


Use the -exec argument to find (or if your system has -print0, you can use find … -print0 | xargs -0 … instead; this is only useful to act on multiple files at once if you need portability to ancient Linux systems or current OpenBSD systems that have -print0 but not -exec … {} +).




ORIGTS=`stat -c "%Y" $f`
# [transform $f]
touch -t $ORIGTS $f



Note that you're missing double quotes around $f (they aren't needed if these are the results of splitting and you haven't changed IFS since then and globbing is turned off, but really, always put double quotes unless you know why you can't leave them on).



This is clumsy and non-portable (stat doesn't exist on all systems, and its arguments are different across the different systems where it exists). touch has a portable option to set a file to the timestamp of another file: touch -r REFERENCE_FILE FILE. I would recommend one of two approaches instead:




  • If you can, first transform the original file into a new file, then call touch -r to set the date of the new file, and finally move the new file into place. It's better to make sure the output is fine before anything happens to the input; otherwise, if the transformation is interrupted for any reason (e.g. a power failure), you'll lose data.

  • If the transformation is a black box that you have no control over, you can use touch -r twice: once to save the date of the original file on an empty temporary file (which will be automatically created), then again after the transformation to restore the date using the temporary file.


Thus:



find /mnt/library/Libra/Libra/Ashfords -name '*.pdf' 
-exec sh -c 'transform "$0" to "$0.tmp" && touch -r "$0" "$0.tmp" && mv -f "$0.tmp" "$0"' {} ;





share|improve this answer































    0














    For some reason I missed the answer about touch -r; if for some strange reason you neither have GNU coreutils’ stat as in the accepted answer nor can use touch -r, here's how to get the timestamp in touch-friendly format with a BSD-like stat.



    % /usr/bin/stat -f '%Sm' johnson                   
    Oct 23 22:51:00 2012
    % /usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson
    201210232251.00
    % touch foo
    % touch -t $(/usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson) foo
    % /usr/bin/stat -f '%Sm' foo
    Oct 23 22:51:00 2012


    But really, just use touch -r:



    % touch foo
    % touch -r johnson foo
    % /usr/bin/stat -f '%Sm' foo
    Oct 23 22:51:00 2012





    share|improve this answer































      0














      I had the same problem, coming from the 'moviemaking' proces'.



      In the example below orig_file.wav is the file with original timestamp, while processed_file.wav is the file with same contents, but wrong timestamp.



      BEFORE:



      localhost $ ls -lh orig_file.wav processed_file.wav
      Jan 23 17:15 processed_file.wav
      Jul 9 2018 orig_file.wav



      THE COMMAND:



      localhost $ touch -t $(date --date=@`stat -f%B orig_file.wav` +%Y%m%d%H%M.%S) processed_file.wav



      AFTER:



      localhost $ ls -lh orig_file.wav processed_file.wav
      Jul 9 2018 processed_file.wav
      Jul 9 2018 orig_file.wav



      NOTES:



      stat in inverted ticks gives you the creation timestamp of the original file as unix epoch time (in seconds). The @ from coreutils converts it to an iso date that date can understand and reformat with YYYYMMDDHHmm.SS so that touch can understand it. I put the date command into $(), as an equivalent of inverted ticks, as they cannot be reused in the same command.






      share|improve this answer








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        5 Answers
        5






        active

        oldest

        votes








        5 Answers
        5






        active

        oldest

        votes









        active

        oldest

        votes






        active

        oldest

        votes









        14














        stat's output is a Unix timestamp, also called seconds since the Epoch.



        All GNU coreutils that accept a date allow you to put a timestamp instead by prefixing the timestamp with an @.



        So try this



        touch -d @$ORIGTS $f


        See coreutils - Seconds since the epoch






        share|improve this answer


























        • ah that explains a lot of timestamps i have seen in linux now! Thanks alot

          – Tim Alexander
          Apr 18 '12 at 15:38
















        14














        stat's output is a Unix timestamp, also called seconds since the Epoch.



        All GNU coreutils that accept a date allow you to put a timestamp instead by prefixing the timestamp with an @.



        So try this



        touch -d @$ORIGTS $f


        See coreutils - Seconds since the epoch






        share|improve this answer


























        • ah that explains a lot of timestamps i have seen in linux now! Thanks alot

          – Tim Alexander
          Apr 18 '12 at 15:38














        14












        14








        14







        stat's output is a Unix timestamp, also called seconds since the Epoch.



        All GNU coreutils that accept a date allow you to put a timestamp instead by prefixing the timestamp with an @.



        So try this



        touch -d @$ORIGTS $f


        See coreutils - Seconds since the epoch






        share|improve this answer















        stat's output is a Unix timestamp, also called seconds since the Epoch.



        All GNU coreutils that accept a date allow you to put a timestamp instead by prefixing the timestamp with an @.



        So try this



        touch -d @$ORIGTS $f


        See coreutils - Seconds since the epoch







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited Apr 18 '12 at 15:28

























        answered Apr 18 '12 at 15:17









        MikelMikel

        39.2k1099125




        39.2k1099125













        • ah that explains a lot of timestamps i have seen in linux now! Thanks alot

          – Tim Alexander
          Apr 18 '12 at 15:38



















        • ah that explains a lot of timestamps i have seen in linux now! Thanks alot

          – Tim Alexander
          Apr 18 '12 at 15:38

















        ah that explains a lot of timestamps i have seen in linux now! Thanks alot

        – Tim Alexander
        Apr 18 '12 at 15:38





        ah that explains a lot of timestamps i have seen in linux now! Thanks alot

        – Tim Alexander
        Apr 18 '12 at 15:38













        8














        touch can use a file's timestamp using the -r option. You might want to output to a different file (I assume below that -if is input file and -of is output file)



        for f in ...; do
        sudo /opt/ABBYYOCR9/abbyyocr9 ... -if $f ... -of $f.new
        touch -r $f $f.new
        mv $f.new $f
        done





        share|improve this answer
























        • +1 for avoiding stat.

          – l0b0
          Apr 18 '12 at 15:39
















        8














        touch can use a file's timestamp using the -r option. You might want to output to a different file (I assume below that -if is input file and -of is output file)



        for f in ...; do
        sudo /opt/ABBYYOCR9/abbyyocr9 ... -if $f ... -of $f.new
        touch -r $f $f.new
        mv $f.new $f
        done





        share|improve this answer
























        • +1 for avoiding stat.

          – l0b0
          Apr 18 '12 at 15:39














        8












        8








        8







        touch can use a file's timestamp using the -r option. You might want to output to a different file (I assume below that -if is input file and -of is output file)



        for f in ...; do
        sudo /opt/ABBYYOCR9/abbyyocr9 ... -if $f ... -of $f.new
        touch -r $f $f.new
        mv $f.new $f
        done





        share|improve this answer













        touch can use a file's timestamp using the -r option. You might want to output to a different file (I assume below that -if is input file and -of is output file)



        for f in ...; do
        sudo /opt/ABBYYOCR9/abbyyocr9 ... -if $f ... -of $f.new
        touch -r $f $f.new
        mv $f.new $f
        done






        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered Apr 18 '12 at 15:30









        glenn jackmanglenn jackman

        51.2k571110




        51.2k571110













        • +1 for avoiding stat.

          – l0b0
          Apr 18 '12 at 15:39



















        • +1 for avoiding stat.

          – l0b0
          Apr 18 '12 at 15:39

















        +1 for avoiding stat.

        – l0b0
        Apr 18 '12 at 15:39





        +1 for avoiding stat.

        – l0b0
        Apr 18 '12 at 15:39











        3















        IFS=$(echo -en "nb")




        Since you're assuming a shell with echo -e, and you have bash in your shebang line anyway, you can use IFS=$'nb'. Making backspace a separator is rather weird. You don't need IFS for what you're doing anyway.




        OLDIFS=$IFS


        IFS=$OLDIFS




        Note that this restores the old value of IFS only if IFS was initially set. If IFS was initially unset, this sets IFS to the empty string, which is completely different. In ksh, bash or zsh, if you need to set IFS temporarily, you can write your code in a function and make IFS local to this function. In other shells, you need to be careful about the unset case.




        `find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`




        Never use command substitution on the output of find.




        • This splits the output at the characters in $IFS. If you set IFS to a newline, then this splits the output at newlines, but you still can't handle file names containing newlines.

        • Not only is the result of command substitution split into words, but then each word is used as a glob pattern. If you files called A[12].pdf, A1.pdf and A2.pdf, you'll end up with A1.pdf A2.pdf A1.pdf A2.pdf. You can turn globbing off with set -f (and back on with set +f), but here (like most of the time) the right way is not to use command substitution.


        Use the -exec argument to find (or if your system has -print0, you can use find … -print0 | xargs -0 … instead; this is only useful to act on multiple files at once if you need portability to ancient Linux systems or current OpenBSD systems that have -print0 but not -exec … {} +).




        ORIGTS=`stat -c "%Y" $f`
        # [transform $f]
        touch -t $ORIGTS $f



        Note that you're missing double quotes around $f (they aren't needed if these are the results of splitting and you haven't changed IFS since then and globbing is turned off, but really, always put double quotes unless you know why you can't leave them on).



        This is clumsy and non-portable (stat doesn't exist on all systems, and its arguments are different across the different systems where it exists). touch has a portable option to set a file to the timestamp of another file: touch -r REFERENCE_FILE FILE. I would recommend one of two approaches instead:




        • If you can, first transform the original file into a new file, then call touch -r to set the date of the new file, and finally move the new file into place. It's better to make sure the output is fine before anything happens to the input; otherwise, if the transformation is interrupted for any reason (e.g. a power failure), you'll lose data.

        • If the transformation is a black box that you have no control over, you can use touch -r twice: once to save the date of the original file on an empty temporary file (which will be automatically created), then again after the transformation to restore the date using the temporary file.


        Thus:



        find /mnt/library/Libra/Libra/Ashfords -name '*.pdf' 
        -exec sh -c 'transform "$0" to "$0.tmp" && touch -r "$0" "$0.tmp" && mv -f "$0.tmp" "$0"' {} ;





        share|improve this answer




























          3















          IFS=$(echo -en "nb")




          Since you're assuming a shell with echo -e, and you have bash in your shebang line anyway, you can use IFS=$'nb'. Making backspace a separator is rather weird. You don't need IFS for what you're doing anyway.




          OLDIFS=$IFS


          IFS=$OLDIFS




          Note that this restores the old value of IFS only if IFS was initially set. If IFS was initially unset, this sets IFS to the empty string, which is completely different. In ksh, bash or zsh, if you need to set IFS temporarily, you can write your code in a function and make IFS local to this function. In other shells, you need to be careful about the unset case.




          `find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`




          Never use command substitution on the output of find.




          • This splits the output at the characters in $IFS. If you set IFS to a newline, then this splits the output at newlines, but you still can't handle file names containing newlines.

          • Not only is the result of command substitution split into words, but then each word is used as a glob pattern. If you files called A[12].pdf, A1.pdf and A2.pdf, you'll end up with A1.pdf A2.pdf A1.pdf A2.pdf. You can turn globbing off with set -f (and back on with set +f), but here (like most of the time) the right way is not to use command substitution.


          Use the -exec argument to find (or if your system has -print0, you can use find … -print0 | xargs -0 … instead; this is only useful to act on multiple files at once if you need portability to ancient Linux systems or current OpenBSD systems that have -print0 but not -exec … {} +).




          ORIGTS=`stat -c "%Y" $f`
          # [transform $f]
          touch -t $ORIGTS $f



          Note that you're missing double quotes around $f (they aren't needed if these are the results of splitting and you haven't changed IFS since then and globbing is turned off, but really, always put double quotes unless you know why you can't leave them on).



          This is clumsy and non-portable (stat doesn't exist on all systems, and its arguments are different across the different systems where it exists). touch has a portable option to set a file to the timestamp of another file: touch -r REFERENCE_FILE FILE. I would recommend one of two approaches instead:




          • If you can, first transform the original file into a new file, then call touch -r to set the date of the new file, and finally move the new file into place. It's better to make sure the output is fine before anything happens to the input; otherwise, if the transformation is interrupted for any reason (e.g. a power failure), you'll lose data.

          • If the transformation is a black box that you have no control over, you can use touch -r twice: once to save the date of the original file on an empty temporary file (which will be automatically created), then again after the transformation to restore the date using the temporary file.


          Thus:



          find /mnt/library/Libra/Libra/Ashfords -name '*.pdf' 
          -exec sh -c 'transform "$0" to "$0.tmp" && touch -r "$0" "$0.tmp" && mv -f "$0.tmp" "$0"' {} ;





          share|improve this answer


























            3












            3








            3








            IFS=$(echo -en "nb")




            Since you're assuming a shell with echo -e, and you have bash in your shebang line anyway, you can use IFS=$'nb'. Making backspace a separator is rather weird. You don't need IFS for what you're doing anyway.




            OLDIFS=$IFS


            IFS=$OLDIFS




            Note that this restores the old value of IFS only if IFS was initially set. If IFS was initially unset, this sets IFS to the empty string, which is completely different. In ksh, bash or zsh, if you need to set IFS temporarily, you can write your code in a function and make IFS local to this function. In other shells, you need to be careful about the unset case.




            `find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`




            Never use command substitution on the output of find.




            • This splits the output at the characters in $IFS. If you set IFS to a newline, then this splits the output at newlines, but you still can't handle file names containing newlines.

            • Not only is the result of command substitution split into words, but then each word is used as a glob pattern. If you files called A[12].pdf, A1.pdf and A2.pdf, you'll end up with A1.pdf A2.pdf A1.pdf A2.pdf. You can turn globbing off with set -f (and back on with set +f), but here (like most of the time) the right way is not to use command substitution.


            Use the -exec argument to find (or if your system has -print0, you can use find … -print0 | xargs -0 … instead; this is only useful to act on multiple files at once if you need portability to ancient Linux systems or current OpenBSD systems that have -print0 but not -exec … {} +).




            ORIGTS=`stat -c "%Y" $f`
            # [transform $f]
            touch -t $ORIGTS $f



            Note that you're missing double quotes around $f (they aren't needed if these are the results of splitting and you haven't changed IFS since then and globbing is turned off, but really, always put double quotes unless you know why you can't leave them on).



            This is clumsy and non-portable (stat doesn't exist on all systems, and its arguments are different across the different systems where it exists). touch has a portable option to set a file to the timestamp of another file: touch -r REFERENCE_FILE FILE. I would recommend one of two approaches instead:




            • If you can, first transform the original file into a new file, then call touch -r to set the date of the new file, and finally move the new file into place. It's better to make sure the output is fine before anything happens to the input; otherwise, if the transformation is interrupted for any reason (e.g. a power failure), you'll lose data.

            • If the transformation is a black box that you have no control over, you can use touch -r twice: once to save the date of the original file on an empty temporary file (which will be automatically created), then again after the transformation to restore the date using the temporary file.


            Thus:



            find /mnt/library/Libra/Libra/Ashfords -name '*.pdf' 
            -exec sh -c 'transform "$0" to "$0.tmp" && touch -r "$0" "$0.tmp" && mv -f "$0.tmp" "$0"' {} ;





            share|improve this answer














            IFS=$(echo -en "nb")




            Since you're assuming a shell with echo -e, and you have bash in your shebang line anyway, you can use IFS=$'nb'. Making backspace a separator is rather weird. You don't need IFS for what you're doing anyway.




            OLDIFS=$IFS


            IFS=$OLDIFS




            Note that this restores the old value of IFS only if IFS was initially set. If IFS was initially unset, this sets IFS to the empty string, which is completely different. In ksh, bash or zsh, if you need to set IFS temporarily, you can write your code in a function and make IFS local to this function. In other shells, you need to be careful about the unset case.




            `find /mnt/library/Libra/Libra/Ashfords -name "*.pdf"`




            Never use command substitution on the output of find.




            • This splits the output at the characters in $IFS. If you set IFS to a newline, then this splits the output at newlines, but you still can't handle file names containing newlines.

            • Not only is the result of command substitution split into words, but then each word is used as a glob pattern. If you files called A[12].pdf, A1.pdf and A2.pdf, you'll end up with A1.pdf A2.pdf A1.pdf A2.pdf. You can turn globbing off with set -f (and back on with set +f), but here (like most of the time) the right way is not to use command substitution.


            Use the -exec argument to find (or if your system has -print0, you can use find … -print0 | xargs -0 … instead; this is only useful to act on multiple files at once if you need portability to ancient Linux systems or current OpenBSD systems that have -print0 but not -exec … {} +).




            ORIGTS=`stat -c "%Y" $f`
            # [transform $f]
            touch -t $ORIGTS $f



            Note that you're missing double quotes around $f (they aren't needed if these are the results of splitting and you haven't changed IFS since then and globbing is turned off, but really, always put double quotes unless you know why you can't leave them on).



            This is clumsy and non-portable (stat doesn't exist on all systems, and its arguments are different across the different systems where it exists). touch has a portable option to set a file to the timestamp of another file: touch -r REFERENCE_FILE FILE. I would recommend one of two approaches instead:




            • If you can, first transform the original file into a new file, then call touch -r to set the date of the new file, and finally move the new file into place. It's better to make sure the output is fine before anything happens to the input; otherwise, if the transformation is interrupted for any reason (e.g. a power failure), you'll lose data.

            • If the transformation is a black box that you have no control over, you can use touch -r twice: once to save the date of the original file on an empty temporary file (which will be automatically created), then again after the transformation to restore the date using the temporary file.


            Thus:



            find /mnt/library/Libra/Libra/Ashfords -name '*.pdf' 
            -exec sh -c 'transform "$0" to "$0.tmp" && touch -r "$0" "$0.tmp" && mv -f "$0.tmp" "$0"' {} ;






            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered Apr 19 '12 at 1:00









            GillesGilles

            533k12810721594




            533k12810721594























                0














                For some reason I missed the answer about touch -r; if for some strange reason you neither have GNU coreutils’ stat as in the accepted answer nor can use touch -r, here's how to get the timestamp in touch-friendly format with a BSD-like stat.



                % /usr/bin/stat -f '%Sm' johnson                   
                Oct 23 22:51:00 2012
                % /usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson
                201210232251.00
                % touch foo
                % touch -t $(/usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson) foo
                % /usr/bin/stat -f '%Sm' foo
                Oct 23 22:51:00 2012


                But really, just use touch -r:



                % touch foo
                % touch -r johnson foo
                % /usr/bin/stat -f '%Sm' foo
                Oct 23 22:51:00 2012





                share|improve this answer




























                  0














                  For some reason I missed the answer about touch -r; if for some strange reason you neither have GNU coreutils’ stat as in the accepted answer nor can use touch -r, here's how to get the timestamp in touch-friendly format with a BSD-like stat.



                  % /usr/bin/stat -f '%Sm' johnson                   
                  Oct 23 22:51:00 2012
                  % /usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson
                  201210232251.00
                  % touch foo
                  % touch -t $(/usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson) foo
                  % /usr/bin/stat -f '%Sm' foo
                  Oct 23 22:51:00 2012


                  But really, just use touch -r:



                  % touch foo
                  % touch -r johnson foo
                  % /usr/bin/stat -f '%Sm' foo
                  Oct 23 22:51:00 2012





                  share|improve this answer


























                    0












                    0








                    0







                    For some reason I missed the answer about touch -r; if for some strange reason you neither have GNU coreutils’ stat as in the accepted answer nor can use touch -r, here's how to get the timestamp in touch-friendly format with a BSD-like stat.



                    % /usr/bin/stat -f '%Sm' johnson                   
                    Oct 23 22:51:00 2012
                    % /usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson
                    201210232251.00
                    % touch foo
                    % touch -t $(/usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson) foo
                    % /usr/bin/stat -f '%Sm' foo
                    Oct 23 22:51:00 2012


                    But really, just use touch -r:



                    % touch foo
                    % touch -r johnson foo
                    % /usr/bin/stat -f '%Sm' foo
                    Oct 23 22:51:00 2012





                    share|improve this answer













                    For some reason I missed the answer about touch -r; if for some strange reason you neither have GNU coreutils’ stat as in the accepted answer nor can use touch -r, here's how to get the timestamp in touch-friendly format with a BSD-like stat.



                    % /usr/bin/stat -f '%Sm' johnson                   
                    Oct 23 22:51:00 2012
                    % /usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson
                    201210232251.00
                    % touch foo
                    % touch -t $(/usr/bin/stat -t '%Y%m%d%H%M.%S' -f '%Sm' johnson) foo
                    % /usr/bin/stat -f '%Sm' foo
                    Oct 23 22:51:00 2012


                    But really, just use touch -r:



                    % touch foo
                    % touch -r johnson foo
                    % /usr/bin/stat -f '%Sm' foo
                    Oct 23 22:51:00 2012






                    share|improve this answer












                    share|improve this answer



                    share|improve this answer










                    answered Jul 7 '18 at 20:12









                    Nicholas RileyNicholas Riley

                    1012




                    1012























                        0














                        I had the same problem, coming from the 'moviemaking' proces'.



                        In the example below orig_file.wav is the file with original timestamp, while processed_file.wav is the file with same contents, but wrong timestamp.



                        BEFORE:



                        localhost $ ls -lh orig_file.wav processed_file.wav
                        Jan 23 17:15 processed_file.wav
                        Jul 9 2018 orig_file.wav



                        THE COMMAND:



                        localhost $ touch -t $(date --date=@`stat -f%B orig_file.wav` +%Y%m%d%H%M.%S) processed_file.wav



                        AFTER:



                        localhost $ ls -lh orig_file.wav processed_file.wav
                        Jul 9 2018 processed_file.wav
                        Jul 9 2018 orig_file.wav



                        NOTES:



                        stat in inverted ticks gives you the creation timestamp of the original file as unix epoch time (in seconds). The @ from coreutils converts it to an iso date that date can understand and reformat with YYYYMMDDHHmm.SS so that touch can understand it. I put the date command into $(), as an equivalent of inverted ticks, as they cannot be reused in the same command.






                        share|improve this answer








                        New contributor




                        dominikz is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                        Check out our Code of Conduct.

























                          0














                          I had the same problem, coming from the 'moviemaking' proces'.



                          In the example below orig_file.wav is the file with original timestamp, while processed_file.wav is the file with same contents, but wrong timestamp.



                          BEFORE:



                          localhost $ ls -lh orig_file.wav processed_file.wav
                          Jan 23 17:15 processed_file.wav
                          Jul 9 2018 orig_file.wav



                          THE COMMAND:



                          localhost $ touch -t $(date --date=@`stat -f%B orig_file.wav` +%Y%m%d%H%M.%S) processed_file.wav



                          AFTER:



                          localhost $ ls -lh orig_file.wav processed_file.wav
                          Jul 9 2018 processed_file.wav
                          Jul 9 2018 orig_file.wav



                          NOTES:



                          stat in inverted ticks gives you the creation timestamp of the original file as unix epoch time (in seconds). The @ from coreutils converts it to an iso date that date can understand and reformat with YYYYMMDDHHmm.SS so that touch can understand it. I put the date command into $(), as an equivalent of inverted ticks, as they cannot be reused in the same command.






                          share|improve this answer








                          New contributor




                          dominikz is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.























                            0












                            0








                            0







                            I had the same problem, coming from the 'moviemaking' proces'.



                            In the example below orig_file.wav is the file with original timestamp, while processed_file.wav is the file with same contents, but wrong timestamp.



                            BEFORE:



                            localhost $ ls -lh orig_file.wav processed_file.wav
                            Jan 23 17:15 processed_file.wav
                            Jul 9 2018 orig_file.wav



                            THE COMMAND:



                            localhost $ touch -t $(date --date=@`stat -f%B orig_file.wav` +%Y%m%d%H%M.%S) processed_file.wav



                            AFTER:



                            localhost $ ls -lh orig_file.wav processed_file.wav
                            Jul 9 2018 processed_file.wav
                            Jul 9 2018 orig_file.wav



                            NOTES:



                            stat in inverted ticks gives you the creation timestamp of the original file as unix epoch time (in seconds). The @ from coreutils converts it to an iso date that date can understand and reformat with YYYYMMDDHHmm.SS so that touch can understand it. I put the date command into $(), as an equivalent of inverted ticks, as they cannot be reused in the same command.






                            share|improve this answer








                            New contributor




                            dominikz is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                            Check out our Code of Conduct.










                            I had the same problem, coming from the 'moviemaking' proces'.



                            In the example below orig_file.wav is the file with original timestamp, while processed_file.wav is the file with same contents, but wrong timestamp.



                            BEFORE:



                            localhost $ ls -lh orig_file.wav processed_file.wav
                            Jan 23 17:15 processed_file.wav
                            Jul 9 2018 orig_file.wav



                            THE COMMAND:



                            localhost $ touch -t $(date --date=@`stat -f%B orig_file.wav` +%Y%m%d%H%M.%S) processed_file.wav



                            AFTER:



                            localhost $ ls -lh orig_file.wav processed_file.wav
                            Jul 9 2018 processed_file.wav
                            Jul 9 2018 orig_file.wav



                            NOTES:



                            stat in inverted ticks gives you the creation timestamp of the original file as unix epoch time (in seconds). The @ from coreutils converts it to an iso date that date can understand and reformat with YYYYMMDDHHmm.SS so that touch can understand it. I put the date command into $(), as an equivalent of inverted ticks, as they cannot be reused in the same command.







                            share|improve this answer








                            New contributor




                            dominikz is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                            Check out our Code of Conduct.









                            share|improve this answer



                            share|improve this answer






                            New contributor




                            dominikz is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                            Check out our Code of Conduct.









                            answered 17 mins ago









                            dominikzdominikz

                            101




                            101




                            New contributor




                            dominikz is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                            Check out our Code of Conduct.





                            New contributor





                            dominikz is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                            Check out our Code of Conduct.






                            dominikz is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                            Check out our Code of Conduct.






























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