Script does not do what it is told to do
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Whenever I run this script -- or several others like it #!/bin/bash # Script to back up all browser files in directory /home/ken/mozilla. STARTDIR=$PWD cd /home/ken tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ - --wildcards -T docs/tarlists/kbrowsers.lst cd "$STARTDIR" it returns the following: ken@Turing:~$ tarkbrowsers tar (child): /media/ssda/backups/kbrowsers.tgz: Cannot open: No such file or directory tar (child): Error is not recoverable: exiting now tar: /media/ssda/backups/kbrowsers.tgz: Cannot write: Broken pipe tar: Child returned status 2 tar: Error is not recoverable: exiting now It is trying to save the tarball to a different portable storage device, ssda, which had failed and consequently is no longer in /etc/fstab. How could such a thing happen? However, if I pull the line with the tar command out of the script and running it independently it does what it is told. If there is something wrong with the script I can't find it. I also tried the script with the second line reading STARTDIR="$PWD"; but that change made no difference, the result was the same. Help please! Regards, Ken -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXbInjgAKCRCU2UnM6QmZ N4QyAJkBqb+i4+4VRA38OWfWHV1GE15AmQCffAk/LjD8QAk48ElZPDk2ReI5RJc= =tfcB -END PGP SIGNATURE-
Re: Script does not do what it is told to do
On Thu, Oct 24, 2019 at 06:37:08PM -0400, Ken Heard wrote: > tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > - --wildcards -T docs/tarlists/kbrowsers.lst Try removing the single '-' at the beginning of the second line... -- Regards Anuradha
Re: Script does not do what it is told to do
Ken Heard wrote: > Whenever I run this script -- or several others like it > > #!/bin/bash > # Script to back up all browser files in directory /home/ken/mozilla. > STARTDIR=$PWD > cd /home/ken > tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > --wildcards -T docs/tarlists/kbrowsers.lst > cd "$STARTDIR" > > it returns the following: > this is not possible because in the script you tell tar to create archive in /media/fde/backups/ > ken@Turing:~$ tarkbrowsers > tar (child): /media/ssda/backups/kbrowsers.tgz: Cannot open: No such > file or directory > tar (child): Error is not recoverable: exiting now > tar: /media/ssda/backups/kbrowsers.tgz: Cannot write: Broken pipe > tar: Child returned status 2 > tar: Error is not recoverable: exiting now > and here you are failing to write /media/ssda/backups/kbrowsers.tgz > It is trying to save the tarball to a different portable storage > device, ssda, which had failed and consequently is no longer in > /etc/fstab. How could such a thing happen? > obviously it is another script or whatever > However, if I pull the line with the tar command out of the script and > running it independently it does what it is told. If there is > something wrong with the script I can't find it. > > I also tried the script with the second line reading STARTDIR="$PWD"; > but that change made no difference, the result was the same. > The question is where do you want to write the data - if on media attached then create entry in /etc/fstab so that you can mount it in consistent way, change the script and the problem will be gone. I have seen all kind of stupid and ugly admin scripts, where the author himself does not know how or why it is or it is not working at the end. regards
Re: Script does not do what it is told to do
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 2019-10-24 7:12 p.m., Anuradha Weeraman wrote: > On Thu, Oct 24, 2019 at 06:37:08PM -0400, Ken Heard wrote: >> tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ - >> --wildcards -T docs/tarlists/kbrowsers.lst > > Try removing the single '-' at the beginning of the second line... In this instance it does not matter whether that '-' is there or not. Pulling that line out of the script and running it independently works both with and without it. Regards, Ken -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXbJHlQAKCRCU2UnM6QmZ N9CyAJ0V2UNi7X6qEj+oTe24JWYyksnm/gCff2SSNSfy8oFTt6wS9R+8f5HupZY= =nMke -END PGP SIGNATURE-
Re: Script does not do what it is told to do
Ken Heard wrote: > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA1 > > On 2019-10-24 7:12 p.m., Anuradha Weeraman wrote: > >> On Thu, Oct 24, 2019 at 06:37:08PM -0400, Ken Heard wrote: >>> tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ - >>> --wildcards -T docs/tarlists/kbrowsers.lst >> >> Try removing the single '-' at the beginning of the second line... > > In this instance it does not matter whether that '-' is there or not. > Pulling that line out of the script and running it independently > works both with and without it. > In the original post I did not see any dash screenshot attached
Re: Script does not do what it is told to do
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 2019-10-24 8:40 p.m., deloptes wrote: > Ken Heard wrote: > >> Whenever I run this script -- or several others like it >> >> #!/bin/bash # Script to back up all browser files in directory >> /home/ken/mozilla. STARTDIR=$PWD cd /home/ken tar -czf >> /media/fde/backups/kbrowsers.tgz --exclude-caches \ --wildcards >> -T docs/tarlists/kbrowsers.lst cd "$STARTDIR" >> >> it returns the following: >> > > this is not possible because in the script you tell tar to create > archive in /media/fde/backups/ Yes, that is the location where I want the archive kbrowsers.tgz to be put. >> ken@Turing:~$ tarkbrowsers tar (child): >> /media/ssda/backups/kbrowsers.tgz: Cannot open: No such file or >> directory tar (child): Error is not recoverable: exiting now tar: >> /media/ssda/backups/kbrowsers.tgz: Cannot write: Broken pipe tar: >> Child returned status 2 tar: Error is not recoverable: exiting >> now >> > > and here you are failing to write > /media/ssda/backups/kbrowsers.tgz /media/ssda/ .. does not exist, neither as a directory or in /etc/fstab >> It is trying to save the tarball to a different portable storage >> device, ssda, which had failed and consequently is no longer in >> /etc/fstab. How could such a thing happen? >> > > obviously it is another script or whatever But how? >> However, if I pull the line with the tar command out of the >> script and running it independently it does what it is told. If >> there is something wrong with the script I can't find it. >> >> I also tried the script with the second line reading >> STARTDIR="$PWD"; but that change made no difference, the result >> was the same. >> > > The question is where do you want to write the data - if on media > attached then create entry in /etc/fstab so that you can mount it > in consistent way, change the script and the problem will be gone. /media/fde is the mount point for the device to which will be written the archive. It is properly mounted, and I can write files to it and read those files. As I said in my original post I am able to write the archive successfully to /media/fde/backups/ by copying the tar command line to a console and read the contents of the tarball. > I have seen all kind of stupid and ugly admin scripts, where the > author himself does not know how or why it is or it is not working > at the end. > > regards Regards, Ken -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXbJjwQAKCRCU2UnM6QmZ NzIJAJ9Ng8JazKDR52yEBcyEoatQBu7PQACcCT5xNctrkAiobqpPGG1Soj9lmCI= =fv+M -END PGP SIGNATURE-
Re: Script does not do what it is told to do
On 2019-10-24 at 18:37, Ken Heard wrote: > Whenever I run this script -- or several others like it > it returns the following: > > ken@Turing:~$ tarkbrowsers > tar (child): /media/ssda/backups/kbrowsers.tgz: Cannot open: No such > file or directory How are you invoking the script? What does $ type tarkbrowsers report? Does running the script with its full path, rather than by the bare name, make any difference? I'm wondering whether there might somehow be another script with this same name, which is in your PATH ahead (and therefore getting invoked instead) of the one you quoted for us. No idea how that might have gotten to be the case, if so, but it's at least worth explicitly ruling out. -- The Wanderer The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man. -- George Bernard Shaw signature.asc Description: OpenPGP digital signature
Re: Script does not do what it is told to do
On Fri, Oct 25, 2019 at 02:40:00AM +0200, deloptes wrote: > Ken Heard wrote: > > > Whenever I run this script -- or several others like it > > > > #!/bin/bash > > # Script to back up all browser files in directory /home/ken/mozilla. > > STARTDIR=$PWD > > cd /home/ken > > tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > > --wildcards -T docs/tarlists/kbrowsers.lst > > cd "$STARTDIR" > > > > it returns the following: > > > > this is not possible because in the script you tell tar to create archive > in /media/fde/backups/ Possibly /media/fde is a (broken) symbolic link to /media/ssda? Besides (but this probably hasn't to do with your failure): what are you trying to achieve with 'STARTDIR=$PWD' and then 'cd "$STARTDIR"'? Cheers -- tomás signature.asc Description: Digital signature
Re: Script does not do what it is told to do
Ken Heard wrote: > the archive. It is properly mounted, and I can write files to it and > read those files. As I said in my original post I am able to write > the archive successfully to /media/fde/backups/ by copying the tar > command line to a console and read the contents of the tarball. > now there is difference - /media/fde/ + /media/ssda/ In the script portion you pasted it is not visible that the disk is dynamically set tar -czf /media/fde/backups/kbrowsers.tgz How does it comes that you have different in the script and in the output I recall that in debian since some time the mount changed from /media/ to /media//
Re: Script does not do what it is told to do
On 24/10/2019 23:37, Ken Heard wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Whenever I run this script -- or several others like it #!/bin/bash # Script to back up all browser files in directory /home/ken/mozilla. STARTDIR=$PWD cd /home/ken tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ - --wildcards -T docs/tarlists/kbrowsers.lst cd "$STARTDIR" it returns the following: ken@Turing:~$ tarkbrowsers tar (child): /media/ssda/backups/kbrowsers.tgz: Cannot open: No such file or directory tar (child): Error is not recoverable: exiting now tar: /media/ssda/backups/kbrowsers.tgz: Cannot write: Broken pipe tar: Child returned status 2 tar: Error is not recoverable: exiting now It is trying to save the tarball to a different portable storage device, ssda, which had failed and consequently is no longer in /etc/fstab. How could such a thing happen? There is nothing inherently wrong with the script, in that it would work if all other things were equal, but they are clearly not. Do an 'ls -l' on '/media/fde/backups', does it reveal anything? It might well do. Using the -C option to tar is preferable to the way you are doing it. So, tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches --wildcards -C /home/ken -T ./docs/tarlists/kbrowsers.lst might be better. You will return to your starting location then, without the need for STARTDIR gubbings. Mike. --
Re: Script does not do what it is told to do
On 10/25/2019 9:16 AM, to...@tuxteam.de wrote: > On Fri, Oct 25, 2019 at 02:40:00AM +0200, deloptes wrote: >> Ken Heard wrote: >> >>> Whenever I run this script -- or several others like it >>> >>> #!/bin/bash >>> # Script to back up all browser files in directory /home/ken/mozilla. >>> STARTDIR=$PWD >>> cd /home/ken >>> tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ >>> --wildcards -T docs/tarlists/kbrowsers.lst >>> cd "$STARTDIR" >>> >>> it returns the following: >>> >> >> this is not possible because in the script you tell tar to create archive >> in /media/fde/backups/ > > Possibly /media/fde is a (broken) symbolic link to /media/ssda? > > Besides (but this probably hasn't to do with your failure): > what are you trying to achieve with 'STARTDIR=$PWD' and then > 'cd "$STARTDIR"'? > Given that you are using bash, my guess is that the below should do what you want: STARTDIR=$(dirname $_) cd $STARTDIR || exit $? -- John Doe
Re: Script does not do what it is told to do
On Fri, Oct 25, 2019 at 09:33:51AM +0200, john doe wrote: > On 10/25/2019 9:16 AM, to...@tuxteam.de wrote: > > On Fri, Oct 25, 2019 at 02:40:00AM +0200, deloptes wrote: > >> Ken Heard wrote: > >> > >>> Whenever I run this script -- or several others like it > >>> > >>> #!/bin/bash > >>> # Script to back up all browser files in directory /home/ken/mozilla. > >>> STARTDIR=$PWD > >>> cd /home/ken > >>> tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > >>> --wildcards -T docs/tarlists/kbrowsers.lst > >>> cd "$STARTDIR" > >>> > >>> it returns the following: > >>> > >> > >> this is not possible because in the script you tell tar to create archive > >> in /media/fde/backups/ > > > > Possibly /media/fde is a (broken) symbolic link to /media/ssda? > > > > Besides (but this probably hasn't to do with your failure): > > what are you trying to achieve with 'STARTDIR=$PWD' and then > > 'cd "$STARTDIR"'? > > > > Given that you are using bash, my guess is that the below should do what > you want: > > STARTDIR=$(dirname $_) > cd $STARTDIR || exit $? My point is that all of this is unnecessary. For one, tar doesn't change the current working directory all by itself. For two, if all of that is run as a subshell, whatever change wouldn't propagate "upstream". Occam's razor. Cheers -- t signature.asc Description: Digital signature
Re: Script does not do what it is told to do
On Fri, Oct 25, 2019 at 08:33:09AM +0100, Michael Howard wrote: > On 24/10/2019 23:37, Ken Heard wrote: > > #!/bin/bash > > # Script to back up all browser files in directory /home/ken/mozilla. > > STARTDIR=$PWD > > cd /home/ken > > tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > > - --wildcards -T docs/tarlists/kbrowsers.lst > > cd "$STARTDIR" > There is nothing inherently wrong with the script, Untrue. I pointed out the flaws last time this subject was discussed on this mailing list. Was that just a few days ago, or was it last week? I don't remember. > in that it would work if > all other things were equal, but they are clearly not. Lots of scripts will work "if certain conditions hold true". That's the fundamental problem here. The script shown here is incredibly fragile, and the author did not correct the flaws that I already pointed out last time. It may "work" under certain conditions. How likely those conditions are to be true, I have no way to know. > Using the -C option to tar is preferable to the way you are doing it. Yup, that was one of the three(?) proposals I made last time around, none of which were followed. *shrug* Not much more I can do when nobody listens to me.
Re: Script does not do what it is told to do
On 25/10/2019 14:11, Greg Wooledge wrote: On Fri, Oct 25, 2019 at 08:33:09AM +0100, Michael Howard wrote: On 24/10/2019 23:37, Ken Heard wrote: #!/bin/bash # Script to back up all browser files in directory /home/ken/mozilla. STARTDIR=$PWD cd /home/ken tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ - --wildcards -T docs/tarlists/kbrowsers.lst cd "$STARTDIR" There is nothing inherently wrong with the script, Untrue. I pointed out the flaws last time this subject was discussed on this mailing list. Was that just a few days ago, or was it last week? I don't remember. Sorry, but it _is_ true. One can't know, nor should one, if the variables and paths are correct, but if they are, i.e. all things being equal, the script is inherrently correct. Of course, it certainly isn't optimal. in that it would work if all other things were equal, but they are clearly not. Lots of scripts will work "if certain conditions hold true". See above. That's the fundamental problem here. The script shown here is incredibly fragile, and the author did not correct the flaws that I already pointed out last time. It may "work" under certain conditions. How likely those conditions are to be true, I have no way to know. I have no idea about when or where the OP may have posted previously. Using the -C option to tar is preferable to the way you are doing it. Yup, that was one of the three(?) proposals I made last time around, none of which were followed. *shrug* Not much more I can do when nobody listens to me. With your attitude, little wonder nobody listens to you. You're probably on the ignore list :) Mike. --
Re: Script does not do what it is told to do
On Fri, Oct 25, 2019 at 02:28:02PM +0100, Michael Howard wrote: > On 25/10/2019 14:11, Greg Wooledge wrote: > > On Fri, Oct 25, 2019 at 08:33:09AM +0100, Michael Howard wrote: > > > On 24/10/2019 23:37, Ken Heard wrote: > > > > #!/bin/bash > > > > # Script to back up all browser files in directory /home/ken/mozilla. > > > > STARTDIR=$PWD > > > > cd /home/ken > > > > tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > > > > - --wildcards -T docs/tarlists/kbrowsers.lst > > > > cd "$STARTDIR" > > > There is nothing inherently wrong with the script, > > Untrue. I pointed out the flaws last time this subject was discussed > > on this mailing list. Was that just a few days ago, or was it last > > week? I don't remember. > > Sorry, but it _is_ true. One can't know, nor should one, if the variables > and paths are correct, but if they are, i.e. all things being equal, the > script is inherrently correct. Of course, it certainly isn't optimal. https://lists.debian.org/debian-user/2019/10/msg00768.html
Re: Script does not do what it is told to do
Hi, Ken Heard wrote: > Whenever I run this script -- or several others like it > [...] > tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > - --wildcards -T docs/tarlists/kbrowsers.lst > [...] > it returns the following: > [...] > tar (child): /media/ssda/backups/kbrowsers.tgz: Cannot open: No such > file or directory > tar (child): Error is not recoverable: exiting now > tar: /media/ssda/backups/kbrowsers.tgz: Cannot write: Broken pipe > [...] > However, if I pull the line with the tar command out of the script and > running it independently it does what it is told. If there is > something wrong with the script I can't find it. The only plausible theories i read so far are: A: The script you run is not the script from which you take the tar command line. B: tar gets somehow convinced that /media/fde/backups/kbrowsers.tgz is actually meant as /media/ssda/backups/kbrowsers.tgz. (This is independent of the flaws of the script, which where pointed out.) So i would try to exclude cause A by adding message output to the script, and cause B by looking at the components of the .tgz path. I.e. i would insert echo "Yes. This is indeed the script." ls -ld /media ls -ld /media/fde ls -ld /media/fde/backups ls -ld /media/fde/backups/kbrowsers.tgz before tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ Then i'd run the script and be curious what happens. Have a nice day :) Thomas
Re: Script does not do what it is told to do
On Fri 25 Oct 2019 at 03:45:45 (+0200), deloptes wrote: > Ken Heard wrote: > > > -BEGIN PGP SIGNED MESSAGE- > > Hash: SHA1 > > > > On 2019-10-24 7:12 p.m., Anuradha Weeraman wrote: > > > >> On Thu, Oct 24, 2019 at 06:37:08PM -0400, Ken Heard wrote: > >>> tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ - > >>> --wildcards -T docs/tarlists/kbrowsers.lst > >> > >> Try removing the single '-' at the beginning of the second line... > > > > In this instance it does not matter whether that '-' is there or not. > > Pulling that line out of the script and running it independently > > works both with and without it. > > > > > In the original post I did not see any dash screenshot attached - And would you blame that on Knode or gmane (I use neither)? It's also noticeable that the said hyphen, which was at the beginning of the line in the OP and was quoted as such in the first reply, had migrated to the end of the line in the OP's reply. That's not exactly helpful when discussing anything to do with tar, notorious for problems caused by its commandline syntax. Does any of the odd punctuation \ - in this post - get affected similarly when lines are kept short? Re the OP, there's a lot of information we aren't a party to; for example, what are /media/fde and /media/ssda - we've only been told what one of them isn't. It also wouldn't be difficult to put set -x into the script, which would show what's being executed as well as confirming that the correct script is being run (because there are "several others like it") by tarkbrowsers. Cheers, David.
Re: Script does not do what it is told to do
On Fri 25 Oct 2019 at 14:28:02 (+0100), Michael Howard wrote: > On 25/10/2019 14:11, Greg Wooledge wrote: > > On Fri, Oct 25, 2019 at 08:33:09AM +0100, Michael Howard wrote: > > > On 24/10/2019 23:37, Ken Heard wrote: > > > > #!/bin/bash > > > > # Script to back up all browser files in directory /home/ken/mozilla. > > > > STARTDIR=$PWD > > > > cd /home/ken > > > > tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > > > > - --wildcards -T docs/tarlists/kbrowsers.lst > > > > cd "$STARTDIR" > > > There is nothing inherently wrong with the script, > > Untrue. I pointed out the flaws last time this subject was discussed > > on this mailing list. Was that just a few days ago, or was it last > > week? I don't remember. > > Sorry, but it _is_ true. One can't know, nor should one, if the > variables and paths are correct, but if they are, i.e. all things > being equal, the script is inherrently correct. Of course, it > certainly isn't optimal. What's the role of the hyphen between the two --switches, please. > > > in that it would work if > > > all other things were equal, but they are clearly not. > > Lots of scripts will work "if certain conditions hold true". > > See above. If one "shouldn't know" about such conditions, then it seems pointless to post this sort of problem on the list. One is better employed in checking one's own assumptions, as Thomas has shown elsewhere in the thread. > > That's the > > fundamental problem here. The script shown here is incredibly fragile, > > and the author did not correct the flaws that I already pointed out > > last time. It may "work" under certain conditions. How likely those > > conditions are to be true, I have no way to know. > > I have no idea about when or where the OP may have posted previously. Four days ago, on this list. Looking back to check the date, I see that the said hyphen had a different, but equally mysterious, role in the OP's script back there. Perhaps you could explain that hyphen at the same time. https://lists.debian.org/debian-user/2019/10/msg00758.html > > > Using the -C option to tar is preferable to the way you are doing it. > > Yup, that was one of the three(?) proposals I made last time around, > > none of which were followed. *shrug* Not much more I can do when > > nobody listens to me. > > With your attitude, little wonder nobody listens to you. You're > probably on the ignore list :) That might explain some of the scripts seen here. I find Greg's comments on scripts very valuable, and they often remind me to check out the pages at http://mywiki.wooledge.org/BashGuide. It would be exaggerating to say that I wait with bated breath for Greg's comments whenever I post a script here myself. Greg's criticism's are far more useful than some of the immaterial English corrections I've seen here. Cheers, David.
Re: Script does not do what it is told to do
On 2019-10-25 at 11:37, David Wright wrote: > On Fri 25 Oct 2019 at 14:28:02 (+0100), Michael Howard wrote: > >> On 25/10/2019 14:11, Greg Wooledge wrote: >>> Untrue. I pointed out the flaws last time this subject was >>> discussed on this mailing list. Was that just a few days ago, or >>> was it last week? I don't remember. >> >> Sorry, but it _is_ true. One can't know, nor should one, if the >> variables and paths are correct, but if they are, i.e. all things >> being equal, the script is inherrently correct. Of course, it >> certainly isn't optimal. > > What's the role of the hyphen between the two --switches, please. I'm not sure whether it can meaningfully serve this function in the specific case given, but generally - particularly, IIRC, for GNU programs - a standalone '-' means something like "treat the data you receive from stdin as if it were the contents of an input file". That wouldn't seem to fit too well with the use of the '-T' option, which appears to mean "read the list of input filenames from the specified file", but it's what I'd normally expect that syntax to mean. -- The Wanderer The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man. -- George Bernard Shaw signature.asc Description: OpenPGP digital signature
Re: Script does not do what it is told to do
On Fri 25 Oct 2019 at 11:49:46 (-0400), The Wanderer wrote: > On 2019-10-25 at 11:37, David Wright wrote: > > On Fri 25 Oct 2019 at 14:28:02 (+0100), Michael Howard wrote: > >> On 25/10/2019 14:11, Greg Wooledge wrote: > > >>> Untrue. I pointed out the flaws last time this subject was > >>> discussed on this mailing list. Was that just a few days ago, or > >>> was it last week? I don't remember. > >> > >> Sorry, but it _is_ true. One can't know, nor should one, if the > >> variables and paths are correct, but if they are, i.e. all things > >> being equal, the script is inherrently correct. Of course, it > >> certainly isn't optimal. > > > > What's the role of the hyphen between the two --switches, please. > > I'm not sure whether it can meaningfully serve this function in the > specific case given, but generally - particularly, IIRC, for GNU > programs - a standalone '-' means something like "treat the data you > receive from stdin as if it were the contents of an input file". > > That wouldn't seem to fit too well with the use of the '-T' option, > which appears to mean "read the list of input filenames from the > specified file", but it's what I'd normally expect that syntax to mean. Sure. - can indicate either of stdin or stdout when it follows -f, stdin after -T, and so on. But I'm asking about its role in this "correct script", and the earlier one where it doesn't even stand alone. (There's no sign of redirection in either script.) Cheers, David.
Re: Script does not do what it is told to do
On 25/10/2019 16:37, David Wright wrote: On Fri 25 Oct 2019 at 14:28:02 (+0100), Michael Howard wrote: On 25/10/2019 14:11, Greg Wooledge wrote: On Fri, Oct 25, 2019 at 08:33:09AM +0100, Michael Howard wrote: On 24/10/2019 23:37, Ken Heard wrote: #!/bin/bash # Script to back up all browser files in directory /home/ken/mozilla. STARTDIR=$PWD cd /home/ken tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ - --wildcards -T docs/tarlists/kbrowsers.lst cd "$STARTDIR" There is nothing inherently wrong with the script, Untrue. I pointed out the flaws last time this subject was discussed on this mailing list. Was that just a few days ago, or was it last week? I don't remember. Sorry, but it _is_ true. One can't know, nor should one, if the variables and paths are correct, but if they are, i.e. all things being equal, the script is inherrently correct. Of course, it certainly isn't optimal. What's the role of the hyphen between the two --switches, please. in that it would work if all other things were equal, but they are clearly not. Lots of scripts will work "if certain conditions hold true". See above. If one "shouldn't know" about such conditions, then it seems pointless to post this sort of problem on the list. One is better employed in checking one's own assumptions, as Thomas has shown elsewhere in the thread. That's the fundamental problem here. The script shown here is incredibly fragile, and the author did not correct the flaws that I already pointed out last time. It may "work" under certain conditions. How likely those conditions are to be true, I have no way to know. I have no idea about when or where the OP may have posted previously. Four days ago, on this list. Looking back to check the date, I see that the said hyphen had a different, but equally mysterious, role in the OP's script back there. Perhaps you could explain that hyphen at the same time. https://lists.debian.org/debian-user/2019/10/msg00758.html Using the -C option to tar is preferable to the way you are doing it. Yup, that was one of the three(?) proposals I made last time around, none of which were followed. *shrug* Not much more I can do when nobody listens to me. With your attitude, little wonder nobody listens to you. You're probably on the ignore list :) That might explain some of the scripts seen here. I find Greg's comments on scripts very valuable, and they often remind me to check out the pages at http://mywiki.wooledge.org/BashGuide. It would be exaggerating to say that I wait with bated breath for Greg's comments whenever I post a script here myself. Greg's criticism's are far more useful than some of the immaterial English corrections I've seen here. Cheers, David. Well good for you. Nice to see Greg as a bodyguard. plonk! In case you don't know and to save you the time replying, that was the sound of you hitting the kill file. Mike. --
Re: Script does not do what it is told to do
Ken Heard writes: > Whenever I run this script -- or several others like it > > #!/bin/bash > # Script to back up all browser files in directory /home/ken/mozilla. > STARTDIR=$PWD > cd /home/ken > tar -czf /media/fde/backups/kbrowsers.tgz --exclude-caches \ > --wildcards -T docs/tarlists/kbrowsers.lst > cd "$STARTDIR" > > it returns the following: > > ken@Turing:~$ tarkbrowsers > tar (child): /media/ssda/backups/kbrowsers.tgz: Cannot open: No such > file or directory > tar (child): Error is not recoverable: exiting now > tar: /media/ssda/backups/kbrowsers.tgz: Cannot write: Broken pipe > tar: Child returned status 2 > tar: Error is not recoverable: exiting now > > It is trying to save the tarball to a different portable storage > device, ssda, which had failed and consequently is no longer in > /etc/fstab. How could such a thing happen? > Please check the output of these commands: which tarkbrowsers cat $(which tarkbrowsers) I suspect your invocation is not running the version of the script you expect. > However, if I pull the line with the tar command out of the script and > running it independently it does what it is told. If there is > something wrong with the script I can't find it. > > I also tried the script with the second line reading STARTDIR="$PWD"; > but that change made no difference, the result was the same. > Try adding an "echo here" line at the beginning of the script and seeing if that shows up. If not, then you know for certain you are not running what you think you are. -- regards, kushal
Re: Script does not do what it is told to do
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 I want at this time to thank all of you for taking the time to provide various suggestions as to how to fix the problems I describe in my original post and in my previous thread 'Signs of hard drive failure?' My reason for the thank you is that early Monday morning 28 October I am leaving for Thailand and will not be back in Toronto until mid-April 2020 and so will not have time for any follow up before I leave. Consequently when my Toronto computer is closed tomorrow it will not be opened or used for the next six months approximately. For those six months I will be using my desktop computer in Thailand which will have been idle from April 2019 to November 2019. I will however summarize here what I have found out so far in Toronto. With regard to possible hard disk failures, with the help of some of you I found out that the internal two hard drives have some life left in them. What had failed however some of my backup portable devices, a 1 tb portable USB hard drive and two of my six high capacity (32-64 tb) USB flash drives, all of which I use for back-ups. What I think had not failed was a SanDisk Extreme 500 (500 gb so they say, but somewhat less) solid state USB portable drive. So for my working files which I will be taking with me I am using one of the 'good' 64 tb USB flash drives mount on /media/fde, and maybe the the SanDisk on /media/ssda. My working files will be compressed into some twenty tarballs written to the fde drive, but not on the ssda for reasons explained below. I am also storing those tarballs in Dropbox. The scripts for these two devices follow. Both are encrypted. - -- #!/bin/bash # Script to open and mount fde sudo cryptsetup luksOpen UUID=26bb9cea-4ac0-47fa-838b-067baeb1936f fde mount /media/fde - -- #!/bin/bash # Script to open and mount ssda sudo cryptsetup luksOpen UUID=347eec80-ede8-4b10-bef6-24065ced3e97 ssda mount /media/ssda - --- As I had found that all these scripts could operate without changing the working directory back and forth from /home/ken I removed from them all the lines changing the working directories which shocked, horrified and amazed many of you. The first script above works; it can open the fde drive. The second one does not work, but it will work if the tar command is extracted from the script and run independently in a virtual terminal. (By the way I have sudo set up to allow me to open every file without password, as this is the only computer on the premises.) The tar scripts now look like this. - --- #!/bin/bash # Script to back up all browser files in directory /home/ken/mozilla. echo here tar -cpzf /media/fde/backups/kbrowsers.tgz --exclude-caches - --wildcards -T docs/tarlists/kbrowsers.lst - --- This one exceptionally has 'echo here" above the tar command at the suggestion of Kushal Kumeran. Also at his request I ran the following two commands: 'which tarkbrowsers' which returned '/home/ken/bin/tarkbrowsers', and 'cat $(which tarkbrowsers)' which returned - --- # Script to back up all browser files in directory /home/ken/mozilla. CURPWD=$PWD cd /home/ken tar -czf /media/ssda/backups/kbrowsers.tgz --exclude-caches - --wildcards -T docs/tarlists/kbrowsers.lst cd $CURPWD - --- As this return includes the change of directories commands it is clear that somewhere there is a series of extraneous scripts but the software is being coy about telling me where they are. As about a fortnight ago all these scripts worked as they should have, it may be possible that the ones which do not work now are those which I did not change in the meantime. So here is where the matter stands now. I will be using these scripts in Thailand and determine whether these idiosyncrasies occur there, where I will have a buster machine instead of the stretch one I am still using in Toronto. So I may be on the thread again in Thailand, and or possibly again in Toronto in April 2020. Regards, Ken Heard -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXbTz8gAKCRCU2UnM6QmZ N1ZGAJ9oiCkQsjTrdBa3HC5p5+CqybdO4ACeIex9comH1W7x1H3mbt7N1Tdm0pI= =VKWL -END PGP SIGNATURE-
Re: Script does not do what it is told to do
On 2019-10-26 at 21:33, Ken Heard wrote: > The tar scripts now look like this. > --- > #!/bin/bash > # Script to back up all browser files in directory /home/ken/mozilla. > echo here > tar -cpzf /media/fde/backups/kbrowsers.tgz --exclude-caches > --wildcards -T docs/tarlists/kbrowsers.lst > --- > This one exceptionally has 'echo here" above the tar command at the > suggestion of Kushal Kumeran. Where is this script located (full path and filename)? If I'm reading things right, you also might want to either put the 'cd /home/ken' line back (no need for the other cd), or use the full path to kbrowsers.lst instead of a relative path; otherwise this won't work right if you run it from any directory which doesn't have that relative path under it. (If kbrowsers.lst has relative paths in it, this might not work correctly from another location without the cd anyway, even if you do use a full path on the command line. I don't have experience with that tar feature myself.) > Also at his request I ran the following two commands: > 'which tarkbrowsers' which returned '/home/ken/bin/tarkbrowsers', and > 'cat $(which tarkbrowsers)' which returned > --- > # Script to back up all browser files in directory /home/ken/mozilla. > CURPWD=$PWD > cd /home/ken > tar -czf /media/ssda/backups/kbrowsers.tgz --exclude-caches > --wildcards -T docs/tarlists/kbrowsers.lst > cd $CURPWD > --- > As this return includes the change of directories commands it is clear > that somewhere there is a series of extraneous scripts but the > software is being coy about telling me where they are. Eh? No, it isn't. It already told you clearly that this latter script is '/home/ken/bin/tarkbrowsers'. Your mail doesn't (seem to?) give us enough information for us to identify where the former of the two given scripts is, but presumably you know where to find that one, since you were able to give its contents here. If you don't want to run this latter version of the script, either move it out of its current directory (which is apparently in your PATH), or replace it with the version you do want to run. (I'm presuming that the newline between '--exclude-caches' and '--wildcards' in each script is an artifact of the mail process, and not present in the actual on-disk script. If it *is* present there, then these are both going to break and not do what you expect.) -- The Wanderer may regret sending this, if recent history is any guide The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man. -- George Bernard Shaw signature.asc Description: OpenPGP digital signature
Re: Script does not do what it is told to do
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 2019-10-26 9:55 p.m., The Wanderer wrote: > On 2019-10-26 at 21:33, Ken Heard wrote: > >> The tar scripts now look like this. >> --- >> #!/bin/bash # Script to back up all browser files in directory >> /home/ken/mozilla. echo here tar -cpzf >> /media/fde/backups/kbrowsers.tgz --exclude-caches --wildcards -T >> docs/tarlists/kbrowsers.lst >> --- This one >> exceptionally has 'echo here" above the tar command at the >> suggestion of Kushal Kumeran. > > Where is this script located (full path and filename)? > > If I'm reading things right, you also might want to either put the > 'cd /home/ken' line back (no need for the other cd), or use the > full path to kbrowsers.lst instead of a relative path; otherwise > this won't work right if you run it from any directory which > doesn't have that relative path under it. > > (If kbrowsers.lst has relative paths in it, this might not work > correctly from another location without the cd anyway, even if you > do use a full path on the command line. I don't have experience > with that tar feature myself.) > >> Also at his request I ran the following two commands: 'which >> tarkbrowsers' which returned '/home/ken/bin/tarkbrowsers', and >> 'cat $(which tarkbrowsers)' which returned >> --- # Script >> to back up all browser files in directory /home/ken/mozilla. >> CURPWD=$PWD cd /home/ken tar -czf >> /media/ssda/backups/kbrowsers.tgz --exclude-caches --wildcards >> -T docs/tarlists/kbrowsers.lst cd $CURPWD >> --- As this >> return includes the change of directories commands it is clear >> that somewhere there is a series of extraneous scripts but the >> software is being coy about telling me where they are. > > Eh? No, it isn't. It already told you clearly that this latter > script is '/home/ken/bin/tarkbrowsers'. > > Your mail doesn't (seem to?) give us enough information for us to > identify where the former of the two given scripts is, but > presumably you know where to find that one, since you were able to > give its contents here. > > If you don't want to run this latter version of the script, either > move it out of its current directory (which is apparently in your > PATH), or replace it with the version you do want to run. > > > (I'm presuming that the newline between '--exclude-caches' and > '--wildcards' in each script is an artifact of the mail process, > and not present in the actual on-disk script. If it *is* present > there, then these are both going to break and not do what you > expect.) > Thank you for your prompt response. I understand what you mean about full and relevant paths. I will have to look into this issue; it may affect the outcome of the script regardless of the computer as both the Toronto and Thailand computers are set up the same way, with the same paths, etc. Regards, Ken -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXbWk7AAKCRCU2UnM6QmZ N/WlAJ4+Nso8uo4X/wLXmj5TMvqSO0uMggCdEphMTf/xIiDxtAJbnQyUV/l/8vA= =7+2G -END PGP SIGNATURE-
