$(pwd) != $(/bin/pwd)
Configuration Information [Automatically generated, do not change]: Machine: i686 OS: linux-gnu Compiler: i686-pc-linux-gnu-gcc Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='i686' -DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i686-pc-linux-gnu' -DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL -DHAVE_CONFIG_H -I. -I. -I./include -I./lib -DDEFAULT_PATH_VALUE='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' -DSTANDARD_UTILS_PATH='/bin:/usr/bin:/sbin:/usr/sbin' -DSYS_BASHRC='/etc/bash/bashrc' -DSYS_BASH_LOGOUT='/etc/bash/bash_logout' -DNON_INTERACTIVE_LOGIN_SHELLS -DSSH_SOURCE_BASHRC -O2 -march=pentium-m -pipe uname output: Linux thinkpad 2.6.31-gentoo-r6 #2 PREEMPT Fri Dec 18 13:16:52 OMST 2009 i686 Intel(R) Pentium(R) M processor 1600MHz GenuineIntel GNU/Linux Machine Type: i686-pc-linux-gnu Bash Version: 4.0 Patch Level: 35 Release Status: release Description: `pwd` may return incorrect value, moreover, `pwd` output differs from /bin/pwd output. Repeat-By: da...@thinkpad ~ $ cd foo da...@thinkpad ~/foo $ touch foo-files da...@thinkpad ~/foo $ ls foo-files da...@thinkpad ~/foo $ mv ~/foo ~/bar da...@thinkpad ~/foo $ ls foo-files da...@thinkpad ~/foo $ echo $PWD /home/darkk/foo da...@thinkpad ~/foo $ pwd /home/darkk/foo da...@thinkpad ~/foo $ /bin/pwd /home/darkk/bar da...@thinkpad ~/foo $ cd . da...@thinkpad ~/bar $ echo $PWD /home/darkk/bar da...@thinkpad ~/bar $ pwd /home/darkk/bar da...@thinkpad ~/bar $ /bin/pwd /home/darkk/bar Strace of this bash session may be found at http://darkk.net.ru/tmp/bash-pwd-bug.strace.log Fix: This problem may be fixed if bash does not optimise number of getcwd() calls, but I'm not sure if the bug is really a _bug_, but not a sort of strange feature.
Re: $(pwd) != $(/bin/pwd)
Leonid Evdokimov schrieb: > This problem may be fixed if bash does not optimise number of getcwd() calls, > but I'm not sure if the bug is really a _bug_, but not a sort of strange > feature. Depends what 'bar' is above, assuming it's a (sym-)link or a bind here: IMHO this is not a bug. There simply is no "one and only absolute path". There's also a nice paper about it from the Plan 9 guys from Bell Labs. J.
Re: $(pwd) != $(/bin/pwd)
Leonid Evdokimov schrieb: > This problem may be fixed if bash does not optimise number of getcwd() calls, > but I'm not sure if the bug is really a _bug_, but not a sort of strange > feature. Sorry, I didn't read carefully enough :) J.
Re: $(pwd) != $(/bin/pwd)
On 1/3/10 8:02 AM, Leonid Evdokimov wrote: > Configuration Information [Automatically generated, do not change]: > Machine: i686 > OS: linux-gnu > Compiler: i686-pc-linux-gnu-gcc > Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='i686' > -DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i686-pc-linux-gnu' > -DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL > -DHAVE_CONFIG_H -I. -I. -I./include -I./lib > -DDEFAULT_PATH_VALUE='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' > -DSTANDARD_UTILS_PATH='/bin:/usr/bin:/sbin:/usr/sbin' > -DSYS_BASHRC='/etc/bash/bashrc' -DSYS_BASH_LOGOUT='/etc/bash/bash_logout' > -DNON_INTERACTIVE_LOGIN_SHELLS -DSSH_SOURCE_BASHRC -O2 -march=pentium-m -pipe > uname output: Linux thinkpad 2.6.31-gentoo-r6 #2 PREEMPT Fri Dec 18 13:16:52 > OMST 2009 i686 Intel(R) Pentium(R) M processor 1600MHz GenuineIntel GNU/Linux > Machine Type: i686-pc-linux-gnu > > Bash Version: 4.0 > Patch Level: 35 > Release Status: release > > Description: > > `pwd` may return incorrect value, moreover, `pwd` output differs from /bin/pwd > output. > > Repeat-By: > > da...@thinkpad ~ $ cd foo > da...@thinkpad ~/foo $ touch foo-files > da...@thinkpad ~/foo $ ls > foo-files > da...@thinkpad ~/foo $ mv ~/foo ~/bar > da...@thinkpad ~/foo $ ls > foo-files > da...@thinkpad ~/foo $ echo $PWD > /home/darkk/foo > da...@thinkpad ~/foo $ pwd > /home/darkk/foo > da...@thinkpad ~/foo $ /bin/pwd > /home/darkk/bar > da...@thinkpad ~/foo $ cd . > da...@thinkpad ~/bar $ echo $PWD > /home/darkk/bar > da...@thinkpad ~/bar $ pwd > /home/darkk/bar > da...@thinkpad ~/bar $ /bin/pwd > /home/darkk/bar > > Strace of this bash session may be found at > http://darkk.net.ru/tmp/bash-pwd-bug.strace.log > > Fix: > > This problem may be fixed if bash does not optimise number of getcwd() calls, > but I'm not sure if the bug is really a _bug_, but not a sort of strange > feature. It's not a bug, nor a "strange feature." Bash maintains a logical view of the file system and the current directory for cd, pwd, and $PWD, as Posix specifies. One of the consequences is that the pathname of the current directory depends on the path used to reach it. If you want to see a physical view of the file system, use `cd -P' or `set -o physical'. Chet -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, ITS, CWRUc...@case.eduhttp://cnswww.cns.cwru.edu/~chet/
