Re: [SLUG] Re: chmod probs. - add. info
On Fri, Apr 10, 2009 at 2:43 PM, Daniel Pittman wrote: > Bernie Pannell writes: > >> try doing the 2 commands in the opposite order, setting everything to >> 664, & then set the directories to 775, ie: >> >> chmod -R 664* >> chmod -R 775 *. > > Epic FAIL! > > The first command will remove the execute bit from every directory, > causing you some incredible grief, and then the second command just > won't work because you no longer have permissions to get at the > contained files sensibly. Homework: mkdir A touch A/B touch A/C chmod u-x A ls -l A rm A/B marvel at the weird. Also, remember, because one day you'll see this behaviour again, and having seen it before will save you from a very baffling 30 minutes while you fight against the machine. > > It /could/ work if you did this: chmod -R ug=rwX,o=rX * > > That uses the GNU chmod specific "only set executable if this is a > directory" flag, Close. Quoting from the man page: execute/search only if the file is a directory or already has execute permission for some user Hrm. "Only if the file is a directory" could probably be worded better. > which works more nicely, but probably isn't exactly the > right answer in the long term. > > Regards, > Daniel > -- > SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ > Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html > -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Re: chmod probs. - add. info
Bernie Pannell writes: > try doing the 2 commands in the opposite order, setting everything to > 664, & then set the directories to 775, ie: > > chmod -R 664* > chmod -R 775 *. Epic FAIL! The first command will remove the execute bit from every directory, causing you some incredible grief, and then the second command just won't work because you no longer have permissions to get at the contained files sensibly. It /could/ work if you did this: chmod -R ug=rwX,o=rX * That uses the GNU chmod specific "only set executable if this is a directory" flag, which works more nicely, but probably isn't exactly the right answer in the long term. Regards, Daniel -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Re: chmod probs. - add. info
Kyle writes: > Have to admit, when I read Daniel's response telling me to use "find", > I cringed. All my experiences with "find" have been very > tortoise-like. But that command came back instantaneously and did the > trick. Heh. I can't blame you: find is probably the most awful of the standard Unix commands, not least because whoever wrote it carefully set out to design the most user-confusing interface ever. It *looks* like find takes a set of arguments, just like any other Unix command, given they all start with a '-', eh? Don't be fooled, though. find(1) actually takes a description, written in a mini-language, that details what to find and what to do when you get there. Ignore the dash and think about it being a language, just like shell, and things become clearer, because now it makes *sense* that the arguments have different meanings in different orders. Unix: proof that just being old, and standard, doesn't make it sane. Regards, Daniel -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Re: chmod probs. - add. info
Thanks all. Have to admit, when I read Daniel's response telling me to use "find", I cringed. All my experiences with "find" have been very tortoise-like. But that command came back instantaneously and did the trick. Thanks again. Kind Regards Kyle James Polley wrote: On Fri, Apr 10, 2009 at 12:32 PM, Kyle wrote: I should clarify; But then if I do a chmod -R 664 *.jpg (and repeat for all other extensions), for some reason the chmod doesn't work. it works in the directory I'm presently in, but doesn't recurse. Yes. Daniel explained why: *.jpg expands to a list of all files whose name ends with .jpg *in the current folder*. There are no directories in that list, so chmod has nothing to recurse into. Daniel provided some find fu which should do what you want (I haven't tried it, just glanced over it). Kind Regards Kyle Kyle wrote: Hi Sluggers, I'm having a bit of grief with chmod and am hoping one of you gurus will set me straight pls. I have a bunch of directories with a bunch of files (pictures) in each. I want to set directories to 775 and files to 664. I can do a chmod -R 775 *. But then if I do a chmod -R 664 *.jpg (and repeat for all other extensions), for some reason the chmod doesn't work. the man page says; 'chmod -R ug=rwxX *' (if I understand it correctly) should change just the directories permissions for owner and group. (and I could do an o=rxX after). But that just works on everything as well. What am I missing? -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Re: chmod probs. - add. info
On Fri, Apr 10, 2009 at 12:32 PM, Kyle wrote: > I should clarify; > > But then if I do a chmod -R 664 *.jpg (and >> repeat for all other extensions), for some reason the chmod doesn't work. > > it works in the directory I'm presently in, but doesn't recurse. Yes. Daniel explained why: *.jpg expands to a list of all files whose name ends with .jpg *in the current folder*. There are no directories in that list, so chmod has nothing to recurse into. Daniel provided some find fu which should do what you want (I haven't tried it, just glanced over it). > > > Kind Regards > > Kyle > > Kyle wrote: >> >> Hi Sluggers, >> >> I'm having a bit of grief with chmod and am hoping one of you gurus will >> set me straight pls. >> >> I have a bunch of directories with a bunch of files (pictures) in each. I >> want to set directories to 775 and files to 664. >> >> I can do a chmod -R 775 *. But then if I do a chmod -R 664 *.jpg (and >> repeat for all other extensions), for some reason the chmod doesn't work. >> >> the man page says; 'chmod -R ug=rwxX *' (if I understand it correctly) >> should change just the directories permissions for owner and group. (and I >> could do an o=rxX after). But that just works on everything as well. >> >> What am I missing? >> > -- > SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ > Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html > -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Re: chmod probs. - add. info
try doing the 2 commands in the opposite order, setting everything to 664, & then set the directories to 775, ie: chmod -R 664* chmod -R 775 *. Regards, Bernie. On Fri, Apr 10, 2009 at 12:32 PM, Kyle wrote: > I should clarify; > > But then if I do a chmod -R 664 *.jpg (and > > repeat for all other extensions), for some reason the chmod doesn't work. > > it works in the directory I'm presently in, but doesn't recurse. > > > Kind Regards > Kyle > -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] chmod probs.
Kyle writes: > I'm having a bit of grief with chmod and am hoping one of you gurus > will set me straight pls. You have a problem with argument globbing on Unix, not chmod, which might explain why you are having trouble finding out what is going wrong. > I have a bunch of directories with a bunch of files (pictures) in > each. I want to set directories to 775 and files to 664. > > I can do a chmod -R 775 *. But then if I do a chmod -R 664 *.jpg (and > repeat for all other extensions), for some reason the chmod doesn't > work. Sure it does, but what actually happens is: 1. You enter 'chmod -R 644 *.jpg' into the shell. 2. The shell expands the '*.jpg' part into a list of files matching that pattern (implicitly in the current directory.) 3. The shell runs 'chmod -R 644 example1.jpg example2.jpg etc.jpg' 4. chmod recurses if any of the arguments are a directory, which none of them are because only *.jpg files were matched. So, everything works as designed, but '-R' doesn't do quite what you thought, and neither does the '*.jpg' argument. Also, if you quote the glob you *still* don't get what you want, because chmod (like almost all Unix commands) doesn't do internal globbing, it expects external globbing, so you would get: ] chmod -R 644 '*.jpg' chmod: cannot access `*.jpg': No such file or directory [...] > What am I missing? find(1), which is used to locate a list of files matching a given set of criteria, allowing you to do something like this: chmod -R 644 `find -name '*.jpg'` (Note the single-quotes around the glob pattern? Without that the shell would expand the pattern, which would cause a syntax error for the find command, and not do what you want.) There is a limit to the number of arguments you can pass to chmod, though, so it is generally speaking better to structure that like this: find -name '*.jpg' | xargs chmod -R 644 That falls apart if any of your filenames have spaces in them, though, since xargs splits on *any* whitespace; to work around that use: find -name '*.jpg' -print0 | xargs -0 chmod -R 644 See the manual pages for the fine detail, obviously. Regards, Daniel -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
[SLUG] Re: chmod probs. - add. info
I should clarify; But then if I do a chmod -R 664 *.jpg (and > repeat for all other extensions), for some reason the chmod doesn't work. it works in the directory I'm presently in, but doesn't recurse. Kind Regards Kyle Kyle wrote: Hi Sluggers, I'm having a bit of grief with chmod and am hoping one of you gurus will set me straight pls. I have a bunch of directories with a bunch of files (pictures) in each. I want to set directories to 775 and files to 664. I can do a chmod -R 775 *. But then if I do a chmod -R 664 *.jpg (and repeat for all other extensions), for some reason the chmod doesn't work. the man page says; 'chmod -R ug=rwxX *' (if I understand it correctly) should change just the directories permissions for owner and group. (and I could do an o=rxX after). But that just works on everything as well. What am I missing? -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
[SLUG] chmod probs.
Hi Sluggers, I'm having a bit of grief with chmod and am hoping one of you gurus will set me straight pls. I have a bunch of directories with a bunch of files (pictures) in each. I want to set directories to 775 and files to 664. I can do a chmod -R 775 *. But then if I do a chmod -R 664 *.jpg (and repeat for all other extensions), for some reason the chmod doesn't work. the man page says; 'chmod -R ug=rwxX *' (if I understand it correctly) should change just the directories permissions for owner and group. (and I could do an o=rxX after). But that just works on everything as well. What am I missing? -- Kind Regards Kyle -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Latest or recommended ways to display Gnome Desktop from Windows boxes.
Hi all Just a follow up and a thanks. I've setup the user with Xming - opening a Putty connection, starting the Xming Windows server and then starting the programs from a putty terminal. Works fast and not sluggish. They mainly use only a few apps (a very pricy IDL being one). I could not get a full Gnome desktop with Xming appearing due to "bad packet length errors" and permissions problems. I just couldn't work that out. I also had probs with vnc. At least this will work for now. Thanks Alex, Ken, Chris, Roger, Jake & David for the suggestions. Michael Lake wrote: I need get get several MS Windows users access to a Fedora Linux box. I have nxserver from nomachine on at present and it works very well but it's limited to just two users. I had tried previously using freenx but I could not get it to work as there seemed to be many library problems in the package. This review here shows a lot more than I wanted to see! http://en.wikipedia.org/wiki/Comparison_of_remote_desktop_software#cite_note-SSHwithX_sessions-4 I basically want a free/open source server for Linux and a free client for Windows for several users to display a Gnome desktop. Plain ssh -X is not sufficient. What have you found that is modern and works well that you have tried? Mike -- Michael Lake Computational Research Centre of Expertise Science Faculty, UTS Ph: 9514 2238 -- UTS CRICOS Provider Code: 00099F DISCLAIMER: This email message and any accompanying attachments may contain confidential information. If you are not the intended recipient, do not read, use, disseminate, distribute or copy this message or attachments. If you have received this message in error, please notify the sender immediately and delete this message. Any views expressed in this message are those of the individual sender, except where the sender expressly, and with authority, states them to be the views of the University of Technology Sydney. Before opening any attachments, please check them for viruses and defects. Think. Green. Do. Please consider the environment before printing this email. -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
