Re: Why /usr/bin/*.dll must be executable?
On 4/23/2012 8:19 PM, Warren Young wrote: On 4/23/2012 6:12 PM, Richard Troy wrote: what on earth would --login have to do with where the dlls are found? Without that, you don't run the profile files[*], so you get the Windows PATH[**] which is clearly insufficient in your situation. Somewhere in one of these files is a line of code that adds the directory containing the problem DLL to your PATH. And the path needed to find DLLs that are provided by the distribution is added in '/etc/profile'. The template for this file can be found in '/etc/defaults/etc'. This file is sourced by default for a login shell. I can't explain why you might see a difference on W7 with this though, unless your non-W7 machines added Cygwin paths in the Windows environment (via cygwin.bat, the control panel that Warren pointed out, or other scripting files that are part of the your process Richard). -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 7:07 AM, Václav Zeman wrote: This is a Windows thing. Another aspect of the Windows Thing which I have not seen discussed yet is the DLL load path: http://goo.gl/VA8yC Since Windows looks for DLLs first in the *.exe directory, this is the most reliable place to put them. Options 2-5 in the list at the page linked above don't really apply here. Cygwin purposely keeps itself nice and segregated from the rest of the system, so installing DLLs under c:\Windows isn't an option, and CWD is simply useless for our purpose here. The only thing stopping us from using the final option in the article (i.e. putting cyg*.dll somewhere else in the PATH) is that it would put the DLLs off in the most fragile location allowed under the rules and it wouldn't solve the OP's problem anyway. The DLLs would still appear in file name completion lists, since that also searches the PATH. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 1:06 PM, Jon TURNEY wrote: 'export EXECIGNORE=*.dll' is a cygwin extension to bash to tell it you don't want to see those pesky dlls. Is there a good reason this isn't in the stock /etc/bash.bashrc? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On Mon, Apr 23, 2012 at 01:02:39PM -0600, Warren Young wrote: On 4/20/2012 1:06 PM, Jon TURNEY wrote: 'export EXECIGNORE=*.dll' is a cygwin extension to bash to tell it you don't want to see those pesky dlls. Is there a good reason this isn't in the stock /etc/bash.bashrc? Not that I can think of. Added for the next release of base-files. -- Primary key fingerprint: AD8F BDC0 5A2C FD5F A179 60E7 F79B AB04 5299 EC56 signature.asc Description: Digital signature
Re: Why /usr/bin/*.dll must be executable?
On 4/23/2012 3:01 PM, Warren Young wrote: Options 2-5 in the list at the page linked above don't really apply here. Cygwin purposely keeps itself nice and segregated from the rest of the system, so installing DLLs under c:\Windows isn't an option, and CWD is simply useless for our purpose here. While the windows and system directories aren't a great place to be putting DLLs that don't belong to the O/S in some way (and indeed Windows tries to discourage it actively in recent versions by keeping it off limits to users without sufficient privileges), why do you think Cygwin apps wouldn't see a DLL it needed if it were in one of these locations? I'm in full agreement that the 16-bit system directory and current directory aren't useful or appropriate options in the context of locations for Cygwin DLLs. -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/23/2012 2:15 PM, Larry Hall (Cygwin) wrote: On 4/23/2012 3:01 PM, Warren Young wrote: Options 2-5 in the list at the page linked above don't really apply here. Cygwin purposely keeps itself nice and segregated from the rest of the system, so installing DLLs under c:\Windows isn't an option, and CWD is simply useless for our purpose here. While the windows and system directories aren't a great place to be putting DLLs that don't belong to the O/S in some way (and indeed Windows tries to discourage it actively in recent versions by keeping it off limits to users without sufficient privileges), why do you think Cygwin apps wouldn't see a DLL it needed if it were in one of these locations? I'm not saying it wouldn't work, I'm just saying that installing Cygwin DLLs under %SYSTEMROOT% would cross the grain of the Cygwin installation philosophy. It would complicate uninstallation, perhaps to the point that someone decides we now need an automatic uninstaller. As it is, manual uninstallation is easy and rare enough that the biggest problem we see with it is people not finding the FAQ item. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On Mon, 23 Apr 2012, Larry Hall (Cygwin) wrote: On 4/23/2012 3:01 PM, Warren Young wrote: Options 2-5 in the list at the page linked above don't really apply here. Cygwin purposely keeps itself nice and segregated from the rest of the system, so installing DLLs under c:\Windows isn't an option, and CWD is simply useless for our purpose here. While the windows and system directories aren't a great place to be putting DLLs that don't belong to the O/S in some way (and indeed Windows tries to discourage it actively in recent versions by keeping it off limits to users without sufficient privileges), why do you think Cygwin apps wouldn't see a DLL it needed if it were in one of these locations? I'm in full agreement that the 16-bit system directory and current directory aren't useful or appropriate options in the context of locations for Cygwin DLLs. Hmmm... I was following this thread hoping to learn something about a problem I was trying to solve wherein I launch a Cygwin-GNU-compiled program and it failed with error while loading shared libraries: ?: cannot open shared object file: No such file or directory. (I think the question mark stands where there would ordinarily be the name of some DLL, but I only received the question mark.) ...It seemed reasonable to think the problem may be related to where the .dll files go, PATH, or some other clue given on the web page cited earlier in this thread regarding the search order for shared libraries, (http://msdn.microsoft.com/en-us/library/windows/desktop/ms682586%28v=vs.85%29.aspx#search_order_for_desktop_applications) but I eventually traced it to something that seems bizarre to me: the use of --login on a call to bash. Pre-Windows 7, this code was known to work fine without the login switch and it drove me banannas until tried --login. I'm wondering; what on earth would --login have to do with where the dlls are found? Thanks, Richard -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/23/2012 6:12 PM, Richard Troy wrote: what on earth would --login have to do with where the dlls are found? Without that, you don't run the profile files[*], so you get the Windows PATH[**] which is clearly insufficient in your situation. Somewhere in one of these files is a line of code that adds the directory containing the problem DLL to your PATH. [*] /etc/profile, ~/.bash_profile, ~/.profile, ~/.bash_login... [**] System control panel Advanced Environment Variables -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 6:10 PM, Mike Kaganski wrote: snip Any code that may be executed (directly or indirectly) must have x under *nix. Windows had tried to make somewhat similar (with the same security concerns in mind) in its NT family, but it had to deal with file systems that have no notion of executability (FAT), so the notion was introduced in NTFS, but is not honored (thus, execute ACL permission is useless in Windows). Huh? It is honored on NTFS. I'm assuming that's what you meant. As Cygwin tries to emulate *nix, I suppose, it explicitly checks executable bit on loading files. So it's not correct to state that this is completely Windows loader thing, but this thing is conceptually correct, so live with it. As I said before, Cygwin doesn't run executables. Cygwin is not an O/S. Windows is the O/S. It has the job of running executables, loading them, following any dependencies (DLLs), and loading those. While Cygwin does emulate POSIX permissions using Windows ACE/ACLs, it is up to Windows to enforce these permissions. But setting permissions is not the same as having some control over the loading executables. Sorry. -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Why /usr/bin/*.dll must be executable?
Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? The error messages are as follows: Administrator@acer /usr/bin $ chmod a-x *.dll Administrator@acer /usr/bin $ lh 18 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: retry: Resource temporarily unavailable 2020930 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: retry: Resource temporarily unavailable 4039235 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: retry: Resource temporarily unavailable 8057832 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: retry: Resource temporarily unavailable 16074662 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: Resource temporarily unavailable DJ -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 2012-4-20 21:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? The error messages are as follows: Administrator@acer /usr/bin $ chmod a-x *.dll Administrator@acer /usr/bin $ lh 18 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: retry: Resource temporarily unavailable 2020930 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: retry: Resource temporarily unavailable 4039235 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: retry: Resource temporarily unavailable 8057832 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: retry: Resource temporarily unavailable 16074662 [main] -bash 4512 fork: child -1 - forked process died unexpectedly, retry 0, exit code -1073741790, errno 11 -bash: fork: Resource temporarily unavailable DJ lh is an alias to 'ls -lh'. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. [...] -- VZ -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 2012-4-20 21:07, Václav Zeman wrote: On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. If this is a windows thing, removing the x bit should not affect Cygwin. Instead, Cygwin is corrupted after removing the x bit. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On Apr 21 00:17, De-Jian Zhao wrote: On 2012-4-20 21:07, Václav Zeman wrote: On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. If this is a windows thing, removing the x bit should not affect Cygwin. Instead, Cygwin is corrupted after removing the x bit. Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Project Co-Leader cygwin AT cygwin DOT com Red Hat -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
RE: Why /usr/bin/*.dll must be executable?
From: Corinna Vinschen Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. So, I had to play with chmod -x cyg*.dll and, of course, it totally hosed Cygwin. I recovered by reinstalling from scratch only after realizing that ATTRIB did not have an option to re- establish X--we're talking XP here. So, as this is a Windows thing, wondering how, through Windows, I could restore execute access to the DLLs. --Ken Nellis
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 1:25 PM, Nellis, Kenneth wrote: From: Corinna Vinschen Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. So, I had to play with chmod -x cyg*.dll and, of course, it totally hosed Cygwin. I recovered by reinstalling from scratch only after realizing that ATTRIB did not have an option to re- establish X--we're talking XP here. So, as this is a Windows thing, wondering how, through Windows, I could restore execute access to the DLLs. What's wrong with chmod +x cyg*.dll? -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 2012-4-21 0:27, Corinna Vinschen wrote: On Apr 21 00:17, De-Jian Zhao wrote: On 2012-4-20 21:07, Václav Zeman wrote: On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. If this is a windows thing, removing the x bit should not affect Cygwin. Instead, Cygwin is corrupted after removing the x bit. Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. Can Windows see the rwx bits assigned by Cygwin to the files? I tried removing the x bit of an executable file blastall.exe (chmod a-x blastall.exe); the file can not be executed under Cygwin, but still can be executed under cmd console of Windows. It seems that Windows does not honor the rwx bits assigned by Cygwin. Is there a detailed description of the starting process of Cygwin system? Or, how does Cygwin interact with *.dll files? After starting Cygwin, I ran chmod a-x /usr/bin/cygperl5_10.dll and perl could not be started any more. This could be cured by ran chmod a+x /usr/bin/cygperl5_10.dll. It seems to me that the Cygwin binary executables will communicate with their corresponding *.dll files when executed. The *.dll provide the required functions and subroutines and that's enough. There is no need to mark *.dll with an x bit. I have no strong background of computer science. Maybe there is some basic knowledge beyond my imagination. Hope you can help disclose it to me. Thanks. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 2012-4-21 1:29, Larry Hall (Cygwin) wrote: On 4/20/2012 1:25 PM, Nellis, Kenneth wrote: From: Corinna Vinschen Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. So, I had to play with chmod -x cyg*.dll and, of course, it totally hosed Cygwin. I recovered by reinstalling from scratch only after realizing that ATTRIB did not have an option to re- establish X--we're talking XP here. So, as this is a Windows thing, wondering how, through Windows, I could restore execute access to the DLLs. What's wrong with chmod +x cyg*.dll? It doesn't work any more. You cannot restart a new terminal, either. You will be trapped here. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
RE: Why /usr/bin/*.dll must be executable?
From: Larry Hall (Cygwin) What's wrong with chmod +x cyg*.dll? As I said, Cygwin was hosed, so I couldn't enter that command. --Ken Nellis
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 1:32 PM, De-Jian Zhao wrote: On 2012-4-21 0:27, Corinna Vinschen wrote: On Apr 21 00:17, De-Jian Zhao wrote: On 2012-4-20 21:07, Václav Zeman wrote: On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. If this is a windows thing, removing the x bit should not affect Cygwin. Instead, Cygwin is corrupted after removing the x bit. Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. Can Windows see the rwx bits assigned by Cygwin to the files? I tried removing the x bit of an executable file blastall.exe (chmod a-x blastall.exe); the file can not be executed under Cygwin, but still can be executed under cmd console of Windows. It seems that Windows does not honor the rwx bits assigned by Cygwin. Is there a detailed description of the starting process of Cygwin system? Or, how does Cygwin interact with *.dll files? After starting Cygwin, I ran chmod a-x /usr/bin/cygperl5_10.dll and perl could not be started any more. This could be cured by ran chmod a+x /usr/bin/cygperl5_10.dll. It seems to me that the Cygwin binary executables will communicate with their corresponding *.dll files when executed. The *.dll provide the required functions and subroutines and that's enough. There is no need to mark *.dll with an x bit. I have no strong background of computer science. Maybe there is some basic knowledge beyond my imagination. Hope you can help disclose it to me. Thanks. Cygwin DLLs are no different than native Windows DLLs when it comes to loading them. The Windows loader is responsible for loading them. So we're stuck with whatever restrictions the Windows loader imposes on Windows apps. -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 1:37 PM, De-Jian Zhao wrote: On 2012-4-21 1:29, Larry Hall (Cygwin) wrote: On 4/20/2012 1:25 PM, Nellis, Kenneth wrote: From: Corinna Vinschen Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. So, I had to play with chmod -x cyg*.dll and, of course, it totally hosed Cygwin. I recovered by reinstalling from scratch only after realizing that ATTRIB did not have an option to re- establish X--we're talking XP here. So, as this is a Windows thing, wondering how, through Windows, I could restore execute access to the DLLs. What's wrong with chmod +x cyg*.dll? It doesn't work any more. You cannot restart a new terminal, either. You will be trapped here. Ah, I didn't realize that Ken did this in /bin. You could use cacls in this case as an alternative to reinstalling. -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 2012-4-21 1:40, Larry Hall (Cygwin) wrote: On 4/20/2012 1:32 PM, De-Jian Zhao wrote: On 2012-4-21 0:27, Corinna Vinschen wrote: On Apr 21 00:17, De-Jian Zhao wrote: On 2012-4-20 21:07, Václav Zeman wrote: On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. If this is a windows thing, removing the x bit should not affect Cygwin. Instead, Cygwin is corrupted after removing the x bit. Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. Can Windows see the rwx bits assigned by Cygwin to the files? I tried removing the x bit of an executable file blastall.exe (chmod a-x blastall.exe); the file can not be executed under Cygwin, but still can be executed under cmd console of Windows. It seems that Windows does not honor the rwx bits assigned by Cygwin. Is there a detailed description of the starting process of Cygwin system? Or, how does Cygwin interact with *.dll files? After starting Cygwin, I ran chmod a-x /usr/bin/cygperl5_10.dll and perl could not be started any more. This could be cured by ran chmod a+x /usr/bin/cygperl5_10.dll. It seems to me that the Cygwin binary executables will communicate with their corresponding *.dll files when executed. The *.dll provide the required functions and subroutines and that's enough. There is no need to mark *.dll with an x bit. I have no strong background of computer science. Maybe there is some basic knowledge beyond my imagination. Hope you can help disclose it to me. Thanks. Cygwin DLLs are no different than native Windows DLLs when it comes to loading them. The Windows loader is responsible for loading them. So we're stuck with whatever restrictions the Windows loader imposes on Windows apps. Yes. But does Windows loader can see the x bit assigned by Cygwin, a quite different OS? At least, *.exe does not respect or even is blind to the -x operation of Cygwin, as abovementioned. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 1:47 PM, De-Jian Zhao wrote: On 2012-4-21 1:40, Larry Hall (Cygwin) wrote: On 4/20/2012 1:32 PM, De-Jian Zhao wrote: On 2012-4-21 0:27, Corinna Vinschen wrote: On Apr 21 00:17, De-Jian Zhao wrote: On 2012-4-20 21:07, Václav Zeman wrote: On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. If this is a windows thing, removing the x bit should not affect Cygwin. Instead, Cygwin is corrupted after removing the x bit. Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. Can Windows see the rwx bits assigned by Cygwin to the files? I tried removing the x bit of an executable file blastall.exe (chmod a-x blastall.exe); the file can not be executed under Cygwin, but still can be executed under cmd console of Windows. It seems that Windows does not honor the rwx bits assigned by Cygwin. Is there a detailed description of the starting process of Cygwin system? Or, how does Cygwin interact with *.dll files? After starting Cygwin, I ran chmod a-x /usr/bin/cygperl5_10.dll and perl could not be started any more. This could be cured by ran chmod a+x /usr/bin/cygperl5_10.dll. It seems to me that the Cygwin binary executables will communicate with their corresponding *.dll files when executed. The *.dll provide the required functions and subroutines and that's enough. There is no need to mark *.dll with an x bit. I have no strong background of computer science. Maybe there is some basic knowledge beyond my imagination. Hope you can help disclose it to me. Thanks. Cygwin DLLs are no different than native Windows DLLs when it comes to loading them. The Windows loader is responsible for loading them. So we're stuck with whatever restrictions the Windows loader imposes on Windows apps. Yes. But does Windows loader can see the x bit assigned by Cygwin, a quite different OS? Cygwin is not an O/S. The basis for Cygwin is the emulation _DLL_, cygwin1.dll. Cygwin executables and DLLs are Windows binaries, subject to whatever limitations the Windows loader has. That's it. If you're not happy about that, you should complain to MS about it. -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 1:47 PM, De-Jian Zhao wrote: snip Oh and... At least, *.exe does not respect or even is blind to the -x operation of Cygwin, as abovementioned. Cygwin creates its Windows ACLs to support POSIX permisssions. See the Cygwin Users Guide for more: http://cygwin.com/cygwin-ug-net/ntsec.html. -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 2012-4-21 1:57, Larry Hall (Cygwin) wrote: On 4/20/2012 1:47 PM, De-Jian Zhao wrote: On 2012-4-21 1:40, Larry Hall (Cygwin) wrote: On 4/20/2012 1:32 PM, De-Jian Zhao wrote: On 2012-4-21 0:27, Corinna Vinschen wrote: On Apr 21 00:17, De-Jian Zhao wrote: On 2012-4-20 21:07, Václav Zeman wrote: On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. If this is a windows thing, removing the x bit should not affect Cygwin. Instead, Cygwin is corrupted after removing the x bit. Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. Can Windows see the rwx bits assigned by Cygwin to the files? I tried removing the x bit of an executable file blastall.exe (chmod a-x blastall.exe); the file can not be executed under Cygwin, but still can be executed under cmd console of Windows. It seems that Windows does not honor the rwx bits assigned by Cygwin. Is there a detailed description of the starting process of Cygwin system? Or, how does Cygwin interact with *.dll files? After starting Cygwin, I ran chmod a-x /usr/bin/cygperl5_10.dll and perl could not be started any more. This could be cured by ran chmod a+x /usr/bin/cygperl5_10.dll. It seems to me that the Cygwin binary executables will communicate with their corresponding *.dll files when executed. The *.dll provide the required functions and subroutines and that's enough. There is no need to mark *.dll with an x bit. I have no strong background of computer science. Maybe there is some basic knowledge beyond my imagination. Hope you can help disclose it to me. Thanks. Cygwin DLLs are no different than native Windows DLLs when it comes to loading them. The Windows loader is responsible for loading them. So we're stuck with whatever restrictions the Windows loader imposes on Windows apps. Yes. But does Windows loader can see the x bit assigned by Cygwin, a quite different OS? Cygwin is not an O/S. The basis for Cygwin is the emulation _DLL_, cygwin1.dll. Cygwin executables and DLLs are Windows binaries, subject to whatever limitations the Windows loader has. That's it. If you're not happy about that, you should complain to MS about it. Then, what limitations does the Windows loader have? As far as I know, there is no x bits for windows, right? How does the chmod a-x affect the file behavior under Windows if this is a Windows thing? I am completely confused. When I ran chmod a-x *.dll, I assumed that these dll files were not executed directly under Cygwin or Windows; they were just some files storing the required functions or something; removing the x bits should not affect the behavior of Cygwin and Windows. If have run chmod a-x on the Windows system dll files, that will lead to the corruption of Windows, right? Thank God. I didn't do that. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/20/2012 2:21 PM, De-Jian Zhao wrote: On 2012-4-21 1:57, Larry Hall (Cygwin) wrote: On 4/20/2012 1:47 PM, De-Jian Zhao wrote: On 2012-4-21 1:40, Larry Hall (Cygwin) wrote: On 4/20/2012 1:32 PM, De-Jian Zhao wrote: On 2012-4-21 0:27, Corinna Vinschen wrote: On Apr 21 00:17, De-Jian Zhao wrote: On 2012-4-20 21:07, Václav Zeman wrote: On 20 April 2012 15:02, De-Jian Zhao wrote: Hi, When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). Since *.dll files are only libraries, they are not necessary to have the attribute of x. Thus, I run the command chmod a-x /usr/bin/*.dll. Unexpectedly, cygwin is corrupted. I closed the terminal and failed to restart Cygwin. I started my older version of Cygwin (I did not deleted it after installing a new version), and added x to the previous *.dll files. The dead Cygwin revived. I am confused why /usr/bin/*.dll should be executable. I thought they were only library files. When I tried to run a dll file, bash says cannot execute binary file. Are there some hidden stories? DLLs are executables thus they need the +x bit. This is a Windows thing. If this is a windows thing, removing the x bit should not affect Cygwin. Instead, Cygwin is corrupted after removing the x bit. Windows requires the x bit for DLLs to be loadable as executable code into the address space of a process. As Václav wrote, it's a Windows thing. Can Windows see the rwx bits assigned by Cygwin to the files? I tried removing the x bit of an executable file blastall.exe (chmod a-x blastall.exe); the file can not be executed under Cygwin, but still can be executed under cmd console of Windows. It seems that Windows does not honor the rwx bits assigned by Cygwin. Is there a detailed description of the starting process of Cygwin system? Or, how does Cygwin interact with *.dll files? After starting Cygwin, I ran chmod a-x /usr/bin/cygperl5_10.dll and perl could not be started any more. This could be cured by ran chmod a+x /usr/bin/cygperl5_10.dll. It seems to me that the Cygwin binary executables will communicate with their corresponding *.dll files when executed. The *.dll provide the required functions and subroutines and that's enough. There is no need to mark *.dll with an x bit. I have no strong background of computer science. Maybe there is some basic knowledge beyond my imagination. Hope you can help disclose it to me. Thanks. Cygwin DLLs are no different than native Windows DLLs when it comes to loading them. The Windows loader is responsible for loading them. So we're stuck with whatever restrictions the Windows loader imposes on Windows apps. Yes. But does Windows loader can see the x bit assigned by Cygwin, a quite different OS? Cygwin is not an O/S. The basis for Cygwin is the emulation _DLL_, cygwin1.dll. Cygwin executables and DLLs are Windows binaries, subject to whatever limitations the Windows loader has. That's it. If you're not happy about that, you should complain to MS about it. Then, what limitations does the Windows loader have? You might want to do a search to find some information about the Windows loader. This isn't really the forum to learn about such things. As far as I know, there is no x bits for windows, right? Windows doesn't use POSIX (rwx) permissions. It uses ACLs (Access Control Lists) for permissions. Cygwin uses the ACLs to simulate POSIX permissions for POSIX apps under it's control. Setting or unsetting x is telling Windows you want to change the executable permissions of the file in question. How does the chmod a-x affect the file behavior under Windows if this is a Windows thing? I am completely confused. When I ran chmod a-x *.dll, I assumed that these dll files were not executed directly under Cygwin or Windows; they were just some files storing the required functions or something; removing the x bits should not affect the behavior of Cygwin and Windows. If have run chmod a-x on the Windows system dll files, that will lead to the corruption of Windows, right? Thank God. I didn't do that. Corruption is not a term I would use but if you're asking me if it's safe for you to go around and change the permissions of any and all files on your system, I would have to recommend against you doing so. Changing the permissions of files on your system isn't something you should do lightly. Think of it as playing around in the registry. If you don't know the consequences, don't do it. -- Larry _ A: Yes. Q: Are you sure? A: Because it reverses the logical flow of conversation. Q: Why is top posting annoying in email? -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html
Re: Why /usr/bin/*.dll must be executable?
On 20/04/2012 14:02, De-Jian Zhao wrote: When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). 'export EXECIGNORE=*.dll' is a cygwin extension to bash to tell it you don't want to see those pesky dlls. See /usr/share/doc/Cygwin/bash.README -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 4/21/2012 5:21 AM, De-Jian Zhao wrote: ... Then, what limitations does the Windows loader have? As far as I know, there is no x bits for windows, right? How does the chmod a-x affect the file behavior under Windows if this is a Windows thing? I am completely confused. When I ran chmod a-x *.dll, I assumed that these dll files were not executed directly under Cygwin or Windows; they were just some files storing the required functions or something; removing the x bits should not affect the behavior of Cygwin and Windows. If have run chmod a-x on the Windows system dll files, that will lead to the corruption of Windows, right? Thank God. I didn't do that. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple The term Executable is not limited to the files that are run directly. It rather shows that this file contains executable code, and in case of DLLs, this is almost always true (unless they are resource-only DLLs; note that sometimes unaware programmers create DLLs wich contain only resources, but fail to create proper resource-only DLLs, ant they still contain loading and unloading code). Any code that may be executed (directly or indirectly) must have x under *nix. Windows had tried to make somewhat similar (with the same security concerns in mind) in its NT family, but it had to deal with file systems that have no notion of executability (FAT), so the notion was introduced in NTFS, but is not honored (thus, execute ACL permission is useless in Windows). As Cygwin tries to emulate *nix, I suppose, it explicitly checks executable bit on loading files. So it's not correct to state that this is completely Windows loader thing, but this thing is conceptually correct, so live with it. -- Best regards, Mike. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Re: Why /usr/bin/*.dll must be executable?
On 2012-4-21 3:06, Jon TURNEY wrote: On 20/04/2012 14:02, De-Jian Zhao wrote: When I type cyg and Tab, many executables starting with cyg are listed (Display all 262 possibilities? (y or n) y). I find that many of them are *.dll libraries under /usr/bin/. This is inconvenient to find the real executable applications (*.exe). 'export EXECIGNORE=*.dll' is a cygwin extension to bash to tell it you don't want to see those pesky dlls. See /usr/share/doc/Cygwin/bash.README Cool! That's just what I need! Thanks, Jon. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
