observation on cygwin file locking, just an FYI

Fri Apr 9 16:07:00 GMT 2004

Assume you have two hosts w/cygwin installed: one that sees script
foobar as a local file and one that is running this same foobar but
through a network drive.
Based on tests, if bash is running the script "foobar", w/foobar
on a remote drive; then while foobar is 
running on this remote box, assume you are now at the host
that has foobar on a local drive:
 o you may *rename* the script to say "foobar~",
 with no effects on the running script
 o you may *delete* the script w/cygwin "rm" with no effects on
 the running script and:
 * in the script's dir, "ls >/dev/null" will say in STDERR 
 ls: foobar~: No such file or directory
 * cmd /c del foobar~ will err out with:
 Access is denied
 * as soon as the running script completes, "foobar~" will
 be unlocked and will be deleted. Your earlier "rm" 
 command is finally "realized".
I assume this is all by design- to emulate UNIX. 
I'm not a developer; so pls enlighten me if my statements above
are in accurate - I only ran one test. What kind of lock is put on
the script while it's running?
See below for my tests - you need
to watch the timestamps in the prompts and hop back and forth between
the bash sessions to follow it. At 10:24:27 foobar is run on the
remote host; foobar is killed w/a ^C at 10:28:11. The 300 line script foobar
just does something like "date;read ans" over and over.
--
regards,
Tom
# --------------------------------------------------------------------
# bash session on our file server w/hostname "mysrvrhost"
# --------------------------------------------------------------------
 # 10:24:18 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ echo [$PS1]; uname -a
 [# \t \d \w \h \u \n\s-\v $ ]
 CYGWIN_NT-5.0 mysrvrhost 1.3.20(0.73/3/2) 2003年02月08日 12:10 i686 unknown unknown Cygwin
 # 10:24:21 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ seq 300|awk '{printf "date;read -p \"prompt no. %0d > \" ans\n",1ドル;}' >foobar # 10:24:36 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ net file |grep foobar 24015085 I:\scm\public\tmp\foobar ADM_TSR 0
 # 10:24:54 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ mv foobar foobar~
 # 10:25:22 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ 
 # 10:25:45 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ net file |grep foobar
 24015085 I:\scm\public\tmp\foobar ADM_TSR 0
 # 10:25:56 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ rm -f foobar~
 # 10:26:13 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ ls -l >/dev/null
 ls: foobar~: No such file or directory
 # 10:26:24 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ xcacls foobar~
 i:\scm\public\tmp\foobar~
 Access is denied.
 # 10:26:40 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ cmd /c del foobar~
 i:\scm\public\tmp\foobar~
 Access is denied.
 # 10:26:57 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ ls -l >/dev/null
 # 10:28:35 Thu Apr 08 /public/tmp mysrvrhost adm_tsr
 -bash-2.05b $ cmd /c del foobar~
 Could Not Find i:\scm\public\tmp\foobar~
# --------------------------------------------------------------------
# bashsession on myclienthost
# myclienthost sees "/public/tmp/foobar" as a network drive
# it's shared out by mysrvrhost
# --------------------------------------------------------------------
 # 10:24:27 Thu Apr 08 /tmp myclienthost adm_tsr
 -bash-2.05b $ bash /public/tmp/foobar
 Thu Apr 8 10:24:43 CDT 2004
 prompt no. 1 >
 Thu Apr 8 10:25:26 CDT 2004
 prompt no. 2 >
 Thu Apr 8 10:25:37 CDT 2004
 prompt no. 3 >
 Thu Apr 8 10:25:37 CDT 2004
 prompt no. 4 >
 Thu Apr 8 10:25:40 CDT 2004
 prompt no. 5 >
 Thu Apr 8 10:27:04 CDT 2004
 prompt no. 6 >
 Thu Apr 8 10:27:04 CDT 2004
 prompt no. 7 >
 Thu Apr 8 10:27:04 CDT 2004
 prompt no. 8 >
 Thu Apr 8 10:27:05 CDT 2004
 prompt no. 9 >
 Thu Apr 8 10:27:08 CDT 2004
 prompt no. 10 >
 Thu Apr 8 10:28:04 CDT 2004
 prompt no. 11 > 
 <snip/did a ^C to abort script>
 # 10:28:11 Thu Apr 08 /tmp myclienthost adm_tsr
 -bash-2.05b $
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