Re: [Lazarus] Process ID
On 09/14/2012 09:26 PM, Marco van de Voort wrote: Yeah. Everybody doing his own parsing of system textfiles is *such* a good principle to build durable applications on *g* -- Haha, Of course it is good that script file programmers can use standard text parsing methods to access system information. But Of course dedicated binary Kernel api calls for all this do exist for more sophisticated purposes. Now any programmer can decide what to use when. - Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On Fri, Sep 14, 2012 at 08:06:38PM +, Mark Morgan Lloyd wrote: > >> In Linux, "everything" is (accessible as if it were) a file (or a > >> directory). This is a _good_thing_. > > > > Yeah. Everybody doing his own parsing of system textfiles is *such* a good > > principle to build durable applications on *g* > > I think it was you who made the point earlier that doing this "the Linux > way" takes multiple syscalls to enumerate the content of directories in > the /proc or /sys tree. That's obviously valid criticism, but at the > same time I'm not sure there's a better way to handle a complex > structure with version- and system-specific elements (example: > /proc/cpuinfo is grossly architecture-specific, even for basic things > like counting the number of CPUs). You miss the point. The /proc structure for the most doesn't even address that since it often packs more than one value into one file. In such it is worse than its direct competitor on Windows, the registry. >but this would be difficult on > account of /proc and /sys being an unstructured mix of stuff defined by > the architecture and stuff changing every nSec. That was exactly the point of my reply to a msg that tried to glorify /proc. > I'm no registry fan, but at least it tries to keep things separate. Indeed. > I wonder whether POSIX has anything instructive to say about this sort > of thing? No. Afaik only the per process part of /proc is standarized, and even then in an optional part. Posix is rarely a solution into anything *nix. It is merely the rock bottom most common denomitor. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Marco van de Voort wrote: On Fri, Sep 14, 2012 at 11:55:52AM +0200, Michael Schnell wrote: Yet another approach of ransacking the whole disk. /proc is not on a disk. It's a virtual file system that generates it's content only on request. In Linux, "everything" is (accessible as if it were) a file (or a directory). This is a _good_thing_. Yeah. Everybody doing his own parsing of system textfiles is *such* a good principle to build durable applications on *g* I think it was you who made the point earlier that doing this "the Linux way" takes multiple syscalls to enumerate the content of directories in the /proc or /sys tree. That's obviously valid criticism, but at the same time I'm not sure there's a better way to handle a complex structure with version- and system-specific elements (example: /proc/cpuinfo is grossly architecture-specific, even for basic things like counting the number of CPUs). It might, I suppose, be possible to build something like the inifiles unit which could parse either the registry (in the case of Windows) or etc+proc+sys+sysctl in the case of unix, but this would be difficult on account of /proc and /sys being an unstructured mix of stuff defined by the architecture and stuff changing every nSec. I'm no registry fan, but at least it tries to keep things separate. I wonder whether POSIX has anything instructive to say about this sort of thing? -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Yeah. Everybody doing his own parsing of system textfiles is *such* a good principle to build durable applications on *g* as far as the text files maintain their structure, well, indeed it is. *g* -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On Fri, Sep 14, 2012 at 11:55:52AM +0200, Michael Schnell wrote: > > Yet another approach of ransacking the whole disk. > > /proc is not on a disk. It's a virtual file system that generates it's > content only on request. > > In Linux, "everything" is (accessible as if it were) a file (or a > directory). This is a _good_thing_. Yeah. Everybody doing his own parsing of system textfiles is *such* a good principle to build durable applications on *g* -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 14-9-2012 15:47, Michael Schnell wrote: > On 09/14/2012 01:47 PM, Reinier Olislagers wrote: >> Sorry, no idea what you're talking about there, especially the >> relationship between your first and second sentence > Maybe I (not an English native speaker) misunderstood your wording. I > understood your "entire" in a way that you wanted _all_possible_ system > calls to be encapsulated in the RTL and LCL. But maybe you meant just > the one functionality in question. Yes, you're right, I meant just the functionality in question. Thanks, Reinier -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 09/14/2012 01:47 PM, Reinier Olislagers wrote: Sorry, no idea what you're talking about there, especially the relationship between your first and second sentence Maybe I (not an English native speaker) misunderstood your wording. I understood your "entire" in a way that you wanted _all_possible_ system calls to be encapsulated in the RTL and LCL. But maybe you meant just the one functionality in question. -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 14-9-2012 13:12, Michael Schnell wrote: > On 09/14/2012 12:43 PM, Reinier Olislagers wrote: >> t encapsulates the entire sorry mess then, and supports Linux, OSX, >> Solaris, AIX... > This very obviously is impossible. But FPC-RTL and LCL always are an > open source work in progress and at any time can easily be enhanced by > any sensible function. Sorry, no idea what you're talking about there, especially the relationship between your first and second sentence. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 09/14/2012 12:43 PM, Reinier Olislagers wrote: t encapsulates the entire sorry mess then, and supports Linux, OSX, Solaris, AIX... This very obviously is impossible. But FPC-RTL and LCL always are an open source work in progress and at any time can easily be enhanced by any sensible function. -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 14 September 2012 12:43, Reinier Olislagers wrote: > On 14-9-2012 12:09, Michael Schnell wrote: > > On 09/14/2012 11:59 AM, Sven Barth wrote: > >> > >> Though I don't want to suggest that syscall I have to state that by > >> default FPC (at least on Linux) always uses the Kernel interface. :) > > I do know this, but this (RTL/LCL) is a "standard library" (like glib, > > though not dynamic). Doing direct syscalls in user code is not that > nice. > > Yet another argument to create (a) function(s) in the RTL that > encapsulates the entire sorry mess then, and supports Linux, OSX, > Solaris, AIX... > and Windows. (Maybe using psxdll.dll?) -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 14-9-2012 12:09, Michael Schnell wrote: > On 09/14/2012 11:59 AM, Sven Barth wrote: >> >> Though I don't want to suggest that syscall I have to state that by >> default FPC (at least on Linux) always uses the Kernel interface. :) > I do know this, but this (RTL/LCL) is a "standard library" (like glib, > though not dynamic). Doing direct syscalls in user code is not that nice. Yet another argument to create (a) function(s) in the RTL that encapsulates the entire sorry mess then, and supports Linux, OSX, Solaris, AIX... -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 09/14/2012 11:59 AM, Sven Barth wrote: Though I don't want to suggest that syscall I have to state that by default FPC (at least on Linux) always uses the Kernel interface. :) I do know this, but this (RTL/LCL) is a "standard library" (like glib, though not dynamic). Doing direct syscalls in user code is not that nice. -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Am 14.09.2012 11:48, schrieb Michael Schnell: On 09/13/2012 06:10 PM, Henry Vermaak wrote: On 13/09/12 17:04, Marco van de Voort wrote: but use of sysctl is strongly discouraged now (in favour of /proc). There not even is a wrapper in glibc for sysctl, so you will need to call it directly via the Kernel interface. Not really recommended ;-) , Though I don't want to suggest that syscall I have to state that by default FPC (at least on Linux) always uses the Kernel interface. :) Regards, Sven -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 09/13/2012 05:48 PM, Jürgen Hestermann wrote: If it's completely in memory then it makes sense. In fact it does not even exist. It's just a standard (straight forward, well structured, programmer-friendly) way to access information. -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 09/13/2012 05:22 PM, Jürgen Hestermann wrote: Yet another approach of ransacking the whole disk. /proc is not on a disk. It's a virtual file system that generates it's content only on request. In Linux, "everything" is (accessible as if it were) a file (or a directory). This is a _good_thing_. -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 09/13/2012 06:10 PM, Henry Vermaak wrote: On 13/09/12 17:04, Marco van de Voort wrote: but use of sysctl is strongly discouraged now (in favour of /proc). There not even is a wrapper in glibc for sysctl, so you will need to call it directly via the Kernel interface. Not really recommended ;-) , -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 13.09.2012 18:14, Mark Morgan Lloyd wrote: Graeme Geldenhuys wrote: On 13/09/12 16:48, Jürgen Hestermann wrote:>> Okay.> Didn't know that. Everything in Linux can be access via "what looks like a file system". eg: com ports, printer ports, usb, sound card etc. Not quite: network (e.g. Ethernet) interfaces and SCSI/USB devices that don't fit a known class have their own namespaces, and despite being shown by e.g. lsof sockets don't have names at all (but information about them might be exposed in /proc). I think that Plan-9 tries to associate absolutely everything with a name, and working from memory the same /might/ apply to curiosities like Helios. And on Windows NT based systems everything is an object :) [Note: I'm talking about the API exposed by the NT kernel here, not the WinAPI] Regards, Sven -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Marco van de Voort wrote: On Thu, Sep 13, 2012 at 09:08:19AM +, Mark Morgan Lloyd wrote: So be fair, I don't think I have ever come across a Linux distro that doesn't include the ps binary as standard. And I have used Linux since 1996. Even *BSD and *Solaris include the ps binary as standard too. Yes, but the ps parameters vary. I'm using this stuff in my FPC build script on Linux and Solaris. Can anybody say what the xBSD situation is? What's in /proc/nnn ? In BSD /proc/ contains [marcov@dragon ~]$ ls /proc/44539 cmdline ctl etype filemap rlimit status [marcov@dragon ~]$ but afaik BSDs can turn /proc off, and this is commonly done so on servers. /proc is only a SysV compatibility feature there, most BSD-own tools work via other interfaces (like sysctl(3)) Turning it off is getting rarer though (probably linux converging). Thanks Marco, very much worth knowing. -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On Thu, Sep 13, 2012 at 03:33:25PM +, Mark Morgan Lloyd wrote: > > Yet another approach of ransacking the whole disk. > > This time just to get a process ID. > > Is that state of the art software developement? > > There is no other way doing it on Linux? > > [Sigh] /proc is a special filesystem which the kernel uses to expose > information about each process. Apart from the fact that it is mounted > into the standard filesystem namespace, it has absolutely nothing to do > with a physical disc. Still it is at least one syscall to enumerate the dir and then 2-3 syscalls (open/read/close) to get a value. Not counting fileexists() which is probably another syscall. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Graeme Geldenhuys wrote: On 13/09/12 16:48, Jürgen Hestermann wrote:>> Okay.> Didn't know that. Everything in Linux can be access via "what looks like a file system". eg: com ports, printer ports, usb, sound card etc. Not quite: network (e.g. Ethernet) interfaces and SCSI/USB devices that don't fit a known class have their own namespaces, and despite being shown by e.g. lsof sockets don't have names at all (but information about them might be exposed in /proc). I think that Plan-9 tries to associate absolutely everything with a name, and working from memory the same /might/ apply to curiosities like Helios. -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 13/09/12 17:04, Marco van de Voort wrote: > On Thu, Sep 13, 2012 at 09:08:19AM +, Mark Morgan Lloyd wrote: >>> So be fair, I don't think I have ever come across a Linux distro that >>> doesn't include the ps binary as standard. And I have used Linux since >>> 1996. Even *BSD and *Solaris include the ps binary as standard too. >> >> Yes, but the ps parameters vary. I'm using this stuff in my FPC build >> script on Linux and Solaris. > >> Can anybody say what the xBSD situation is? What's in /proc/nnn ? > > In BSD /proc/ contains > > [marcov@dragon ~]$ ls /proc/44539 > cmdline ctl etype filemap rlimit status > [marcov@dragon ~]$ > > but afaik BSDs can turn /proc off, and this is commonly done so on servers. > > /proc is only a SysV compatibility feature there, > most BSD-own tools work via other interfaces (like sysctl(3)) It's also possible to do this on linux with sysctl (I've got some c source somewhere), but use of sysctl is strongly discouraged now (in favour of /proc). Henry -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Jürgen Hestermann wrote: Am 2012-09-13 17:33, schrieb Mark Morgan Lloyd: [Sigh] /proc is a special filesystem which the kernel uses to expose information about each process. Apart from the fact that it is mounted into the standard filesystem namespace, it has absolutely nothing to do with a physical disc. Okay. Didn't know that. If it's completely in memory then it makes sense. There are even more borderline cases: things like unix-domain sockets (named pipes) exist as a named entity on disc, but once opened are simply a handle in memory. -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On Thu, Sep 13, 2012 at 09:08:19AM +, Mark Morgan Lloyd wrote: > > So be fair, I don't think I have ever come across a Linux distro that > > doesn't include the ps binary as standard. And I have used Linux since > > 1996. Even *BSD and *Solaris include the ps binary as standard too. > > Yes, but the ps parameters vary. I'm using this stuff in my FPC build > script on Linux and Solaris. > Can anybody say what the xBSD situation is? What's in /proc/nnn ? In BSD /proc/ contains [marcov@dragon ~]$ ls /proc/44539 cmdline ctl etype filemap rlimit status [marcov@dragon ~]$ but afaik BSDs can turn /proc off, and this is commonly done so on servers. /proc is only a SysV compatibility feature there, most BSD-own tools work via other interfaces (like sysctl(3)) Turning it off is getting rarer though (probably linux converging). -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On Thu, Sep 13, 2012 at 09:09:04AM +0100, Graeme Geldenhuys wrote: > On 13/09/12 08:42, Mark Morgan Lloyd wrote: > > i) That the ps binary is available. > > So be fair, I don't think I have ever come across a Linux distro that > doesn't include the ps binary as standard. And I have used Linux since > 1996. Even *BSD and *Solaris include the ps binary as standard too. Afaik many haven't. They usually symlink 'ps' it to busybox, which implements basic info only. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 13/09/12 16:48, Jürgen Hestermann wrote: Okay. Didn't know that. Everything in Linux can be access via "what looks like a file system". eg: com ports, printer ports, usb, sound card etc. Graeme. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Kaj Mikkelsen wrote: Mark Morgan Lloyd wrote: Wrong. I've got a terminal session connected to a Solaris 10 system on my desk at the moment (because I'm trying to debug some LOM issues), and /proc is fine. However, it's worth remembering that non-Linux implementations tend to have less in the /proc tree than Linux, and that the Linux kernel developers are trying to move towards this model. I maintain SunOS 4, Solaris 7,8 and 9. I am pretty sure /proc is very invalidated if it exists on the SunOS platform. On newer version it requires root privileges. And I've just fired up a Solaris 10 system: -bash-3.00$ uname -a SunOS pye-dev-09 5.10 Generic_118833-17 sun4u sparc SUNW,Sun-Fire-280R Solaris -bash-3.00$ ls -l /proc/$PPID/fd total 0 c- 1 rootsys 13, 2 Sep 13 15:31 0 c- 1 rootsys 13, 2 Sep 13 15:31 1 c- 0 rootroot 23, 1 Sep 13 15:38 10 p- 0 markMLl staff 0 Sep 13 15:33 11 c- 0 rootroot 23, 1 Sep 13 15:38 12 c- 1 rootsys 13, 2 Sep 13 15:31 2 D- 1 rootroot 0 Sep 13 15:30 3 s- 0 rootroot 0 Sep 13 15:38 4 p- 0 markMLl staff 0 Sep 13 15:33 5 p- 0 markMLl staff 0 Sep 13 15:33 6 p- 0 markMLl staff 0 Sep 13 15:33 7 s- 0 rootroot 0 Sep 13 15:33 8 c- 0 rootroot 23, 1 Sep 13 15:38 9 -bash-3.00$ ls -l /proc/$PPID/path 2>/dev/null |grep a.out lrwxrwxrwx 1 markMLl staff 0 Sep 13 15:33 a.out -> /usr/lib/ssh/sshd Now you'll obviously need elevated privileges to look at properties of processes that you're not related to, but in other cases /proc (or directly comparable resources) is available- otherwise where do you think things like ps get their info? So if you want to trump that I suggest getting hold of a copy of Solaris 11 (or OpenIndiana or whatever it calls itself these days) and seeing what restrictions it adds (and then check out Lazarus on it and update any bits of http://wiki.lazarus.freepascal.org/Lazarus_on_Solaris that merit attention :-) -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Am 2012-09-13 17:33, schrieb Mark Morgan Lloyd: [Sigh] /proc is a special filesystem which the kernel uses to expose information about each process. Apart from the fact that it is mounted into the standard filesystem namespace, it has absolutely nothing to do with a physical disc. Okay. Didn't know that. If it's completely in memory then it makes sense. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Jürgen Hestermann wrote: Am 2012-09-13 10:11, schrieb Michael Schnell: IMHO its easier and more straight forward to do the functionality of "pidof" directly in pascal code: - do a loop with a findnext() to handle all directories within "/proc" - in each of them test if a file "cmdline" exists - read cmdline in a staring - if this denotes the process you mean to access the directory name is the PID Oh my god! Yet another approach of ransacking the whole disk. This time just to get a process ID. Is that state of the art software developement? There is no other way doing it on Linux? [Sigh] /proc is a special filesystem which the kernel uses to expose information about each process. Apart from the fact that it is mounted into the standard filesystem namespace, it has absolutely nothing to do with a physical disc. -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Am 2012-09-13 10:11, schrieb Michael Schnell: IMHO its easier and more straight forward to do the functionality of "pidof" directly in pascal code: - do a loop with a findnext() to handle all directories within "/proc" - in each of them test if a file "cmdline" exists - read cmdline in a staring - if this denotes the process you mean to access the directory name is the PID Oh my god! Yet another approach of ransacking the whole disk. This time just to get a process ID. Is that state of the art software developement? There is no other way doing it on Linux? -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Mark Morgan Lloyd wrote: >>Wrong. I've got a terminal session connected to a Solaris 10 system on my desk at the moment (because I'm trying to debug some LOM issues), and /proc is fine. However, it's worth remembering that non-Linux implementations tend to have less in the /proc tree than Linux, and that the Linux kernel developers are trying to move towards this model. I maintain SunOS 4, Solaris 7,8 and 9. I am pretty sure /proc is very invalidated if it exists on the SunOS platform. On newer version it requires root privileges. /Kaj -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 09/13/2012 10:48 AM, Antonio Fortuny wrote: This way of solving the problem seems to be the best when the goal is to retrieve the PID of a given program. As the /proc directory is tidy coupled to the kernel it's probably the fastest Yep This is what I gonna implement for the second part of my development. You additionally might want to take a look at the C source code of "pidof". Happy open-sourcing :) -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Graeme Geldenhuys hat am 13. September 2012 um 11:19 geschrieben: > On 13/09/12 10:01, Mattias Gaertner wrote: > > > > Yes, but its parameters vary. > > Between Linux distros? Yes. For examples some embedded Linux and chroot jails. > I know they vary between FreeBSD, Solaris and > Linux. But I think they are all the same on various Linux distros. The > original poster specifically mentioned usage under Linux, so again I > think he can safely use ps without problems in his environment. He might safely use them, if he knows his target platforms. Mattias -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Graeme Geldenhuys wrote: On 13/09/12 10:08, Mark Morgan Lloyd wrote: Yes, but the ps parameters vary. I'm using this stuff in my FPC build script on Linux and Solaris. Yes, they vary between Linux, Solaris and FreeBSD, but as far as I know, the do not vary between Linux distros. The original poster specifically mentioned his usage under Linux only. They /definitely/ vary, although I'm not sure it's directly relevant to the OP's problem. As an example, ps's --ppid option was introduced at v3 and I still have live systems around here running v2. -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 13/09/12 10:08, Mark Morgan Lloyd wrote: Yes, but the ps parameters vary. I'm using this stuff in my FPC build script on Linux and Solaris. Yes, they vary between Linux, Solaris and FreeBSD, but as far as I know, the do not vary between Linux distros. The original poster specifically mentioned his usage under Linux only. Graeme. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 13/09/12 10:01, Mattias Gaertner wrote: Yes, but its parameters vary. Between Linux distros? I know they vary between FreeBSD, Solaris and Linux. But I think they are all the same on various Linux distros. The original poster specifically mentioned usage under Linux, so again I think he can safely use ps without problems in his environment. Graeme. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Antonio Fortuny wrote:
Hi guys.
Thanks to all anyway for answering.
I've found two nice solutions to solve my problem.
To be honest I've to mention that what my function receives a paramater
which is a PID and the function has to check if that process is still
running returning a value. Sorry for any misunderstanding. I agree that
my question was ambigous from that point of view.
This is also a fairly common requirement when a program leaves lock
files in a directory or a unix-domain socket etc. in /tmp or ~
# ls -l /var/run/*ttyS*
-rw-r--r-- 1 root root 4 Sep 6 13:46 /var/run/mgetty.pid.ttyS11
-rw-r--r-- 1 root root 6 Sep 8 18:46 /var/run/mgetty.pid.ttyS6
2. use kill with signal 0
uses BaseUnix;
if FpKill(wPID, 0) = 0 then
MessageDlg('OK', 'FpPid process is running', mtInformation, [mbOK], 0)
else
MessageDlg('OK', 'FpPid process is NOT running', mtError, [mbOK], 0);
I guess that solution 2 is the best as it asks immediately the kernel.
I agree.
--
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk
[Opinions above are the author's, not those of his employers or colleagues]
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Re: [Lazarus] Process ID
Graeme Geldenhuys wrote: On 13/09/12 08:42, Mark Morgan Lloyd wrote: i) That the ps binary is available. So be fair, I don't think I have ever come across a Linux distro that doesn't include the ps binary as standard. And I have used Linux since 1996. Even *BSD and *Solaris include the ps binary as standard too. Yes, but the ps parameters vary. I'm using this stuff in my FPC build script on Linux and Solaris. Can anybody say what the xBSD situation is? What's in /proc/nnn ? -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Kaj Mikkelsen wrote: I have never seen a Linux or Unix system that did not have ps installed. No, but I've seen it not working because /proc wasn't available- which gives you absolutely no advantage attempting to use ps compared with going to /proc directly (i.e. you get an unparseable error message from ps compared with a clear indication that there's nothing mounted on /proc). Unless we are talking embedded systems or similar. Unix systems (Solaris, AIX, SCO ) do not have the /proc file system, at least it is not usable. Wrong. I've got a terminal session connected to a Solaris 10 system on my desk at the moment (because I'm trying to debug some LOM issues), and /proc is fine. However, it's worth remembering that non-Linux implementations tend to have less in the /proc tree than Linux, and that the Linux kernel developers are trying to move towards this model. I would say that Solaris appears not to have /proc/nnn/cmdline, I think the equivalent is in /proc/nnn/psinfo. Irrespective of which, I still think it's better practice to either go directly to /proc or to look for a portable library- I don't know whether there's a POSIX API for this in the same way that there's a POSIX-compliant capabilities library on top of the Linux/Solaris/etc. kernel. -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Graeme Geldenhuys hat am 13. September 2012 um 10:09 geschrieben: > On 13/09/12 08:42, Mark Morgan Lloyd wrote: > > i) That the ps binary is available. > > So be fair, I don't think I have ever come across a Linux distro that > doesn't include the ps binary as standard. And I have used Linux since > 1996. Even *BSD and *Solaris include the ps binary as standard too. > > So I think it is quite safe to assume the ps binary will be available on > a Linux system. Yes, but its parameters vary. Mattias -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
IMHO its easier and more straight forward to do the functionality of "pidof" directly in pascal code: - do a loop with a findnext() to handle all directories within "/proc" - in each of them test if a file "cmdline" exists - read cmdline in a staring - if this denotes the process you mean to access the directory name is the PID This way of solving the problem seems to be the best when the goal is to retrieve the PID of a given program. As the /proc directory is tidy coupled to the kernel it's probably the fastest This is what I gonna implement for the second part of my development. Antonio. -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 13-9-2012 10:09, Graeme Geldenhuys wrote: > On 13/09/12 08:42, Mark Morgan Lloyd wrote: >> i) That the ps binary is available. > > So be fair, I don't think I have ever come across a Linux distro that > doesn't include the ps binary as standard. And I have used Linux since > 1996. Even *BSD and *Solaris include the ps binary as standard too. > > So I think it is quite safe to assume the ps binary will be available on > a Linux system. Agreed. The fact that these pesky command line arguments do differ may be an *ahem* argument to wrap up this functionality in an FPC library function so the user does not need to remember/fiddle with/update his code for the various differences and the code will run on e.g. OSX, Linux, Solaris, AIX without modifications. ... and if, for some reason, ps functionality is implemented in another way (e.g. no ps but /proc filesystem is available), obviously this library function could be extended... Of course, this all depends on reliable OS detection etc, which, looking at earlier discussions here and going from experience, is not that easy either. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Michael Schnell wrote: >IMHO its easier and more straight forward to do the functionality of "pidof" directly in pascal code: >- do a loop with a findnext() to handle all directories within "/proc" >- in each of them test if a file "cmdline" exists >- read cmdline in a staring >- if this denotes the process you mean to access the directory name is the PID All depending on what was the purpose. I thought the goal was to find all processes owned by a specific user, but have now leaned this was not the case. Using the /proc file system eliminate the need for a call to the underlying OS which is good. /Kaj ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Mark Morgan Lloyd Wrote: >Please use the same quoting convention as the messages you are responding to. The thread was already growing downwards, and adding a message to the top is inappropriate. >In my experience, using ps etc. is wrong since apart from the efficiency aspect it makes several assumptions: >i) That the ps binary is available. >ii) That the command-line options you need are universally implemented. >iii) That (at least in the case of Linux) the /proc filesystem is available. >I think that it's probably more portable to go straight to the values available in /proc, if you can't read them then it's unlikely that ps would show you much more. I have never seen a Linux or Unix system that did not have ps installed. Unless we are talking embedded systems or similar. Unix systems (Solaris, AIX, SCO ) do not have the /proc file system, at least it is not usable. So living in a heterogeneous world I would prefer the ps, although I know the options (aux in this case) varies from system to system. Whatever works for the user and he/she finds easiest to use is the correct way ;-) /Kaj -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 09/13/2012 07:36 AM, Kaj Mikkelsen wrote: If I understand your question correct, you are asking for a lazarus function. I don't think that exists. But you can use the TProcess to execute a linux command and grab the output. IMHO its easier and more straight forward to do the functionality of "pidof" directly in pascal code: - do a loop with a findnext() to handle all directories within "/proc" - in each of them test if a file "cmdline" exists - read cmdline in a staring - if this denotes the process you mean to access the directory name is the PID -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On 13/09/12 08:42, Mark Morgan Lloyd wrote: i) That the ps binary is available. So be fair, I don't think I have ever come across a Linux distro that doesn't include the ps binary as standard. And I have used Linux since 1996. Even *BSD and *Solaris include the ps binary as standard too. So I think it is quite safe to assume the ps binary will be available on a Linux system. Graeme. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
Hi guys.
Thanks to all anyway for answering.
I've found two nice solutions to solve my problem.
To be honest I've to mention that what my function receives a paramater
which is a PID and the function has to check if that process is still
running returning a value. Sorry for any misunderstanding. I agree that
my question was ambigous from that point of view.
1. Look at /proc/ as /proc has dr-xr-xr-x permissions, like
if DirectoryExistsUTF8(Format('/proc/%d', [wPID])) then
MessageDlg('OK', 'process is running', mtInformation, [mbOK], 0)
else
MessageDlg('OK', 'process is NOT running', mtError, [mbOK], 0);
2. use kill with signal 0
uses BaseUnix;
if FpKill(wPID, 0) = 0 then
MessageDlg('OK', 'FpPid process is running', mtInformation, [mbOK], 0)
else
MessageDlg('OK', 'FpPid process is NOT running', mtError, [mbOK], 0);
I guess that solution 2 is the best as it asks immediately the kernel.
Antonio.
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Re: [Lazarus] Process ID
Kaj Mikkelsen wrote: If I understand your question correct, you are asking for a lazarus function. I don't think that exists. But you can use the TProcess to execute a linux command and grab the output. Pidof will give you the processed of a specific program. Ps is much more multipurpose, and it does *not* requires you to be root. At leat not in RedHat/Centos You can use the following command to find all processes for a specific user (using kmi as an example): ps aux | grep -w ^kmi Please use the same quoting convention as the messages you are responding to. The thread was already growing downwards, and adding a message to the top is inappropriate. In my experience, using ps etc. is wrong since apart from the efficiency aspect it makes several assumptions: i) That the ps binary is available. ii) That the command-line options you need are universally implemented. iii) That (at least in the case of Linux) the /proc filesystem is available. I think that it's probably more portable to go straight to the values available in /proc, if you can't read them then it's unlikely that ps would show you much more. -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
If I understand your question correct, you are asking for a lazarus function. I don't think that exists. But you can use the TProcess to execute a linux command and grab the output. Pidof will give you the processed of a specific program. Ps is much more multipurpose, and it does *not* requires you to be root. At leat not in RedHat/Centos You can use the following command to find all processes for a specific user (using kmi as an example): ps aux | grep -w ^kmi /Kaj -Original Message- From: ik [mailto:ido...@gmail.com] Sent: 12. september 2012 19:37 To: Lazarus mailing list Subject: Re: [Lazarus] Process ID On Wed, Sep 12, 2012 at 7:22 PM, Ian Godman wrote: > You can use the ps command to list process status. Many option so try > man ps or info ps for further information. > > To get process info for other users you need root privilege, sudo ps > should do that. "pidof" is much more effective for it. > > Also top will tell you the running processes and how much memory / cpu > each is using. Use q to exit. > > > Ian > > On 12/09/12 15:59, Antonio Fortuny wrote: >> Hi list. >> >> Which function to use in Linux (if any) to get the process ID of a >> running process which is not mine. GetProcessID retrieves my own >> process ID. >> I'm using OpenProcess in Win >> >> Antonio. >> >> >> >> -- >> ___ >> Lazarus mailing list >> Lazarus@lists.lazarus.freepascal.org >> http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus >> >> > > -- > ___ > Lazarus mailing list > Lazarus@lists.lazarus.freepascal.org > http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
On Wed, Sep 12, 2012 at 7:22 PM, Ian Godman wrote: > You can use the ps command to list process status. Many option so try > man ps or info ps for further information. > > To get process info for other users you need root privilege, sudo ps > should do that. "pidof" is much more effective for it. > > Also top will tell you the running processes and how much memory / cpu > each is using. Use q to exit. > > > Ian > > On 12/09/12 15:59, Antonio Fortuny wrote: >> Hi list. >> >> Which function to use in Linux (if any) to get the process ID of a >> running process which is not mine. GetProcessID retrieves my own process >> ID. >> I'm using OpenProcess in Win >> >> Antonio. >> >> >> >> -- >> ___ >> Lazarus mailing list >> Lazarus@lists.lazarus.freepascal.org >> http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus >> >> > > -- > ___ > Lazarus mailing list > Lazarus@lists.lazarus.freepascal.org > http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
You can use the ps command to list process status. Many option so try man ps or info ps for further information. To get process info for other users you need root privilege, sudo ps should do that. Also top will tell you the running processes and how much memory / cpu each is using. Use q to exit. Ian On 12/09/12 15:59, Antonio Fortuny wrote: > Hi list. > > Which function to use in Linux (if any) to get the process ID of a > running process which is not mine. GetProcessID retrieves my own process > ID. > I'm using OpenProcess in Win > > Antonio. > > > > -- > ___ > Lazarus mailing list > Lazarus@lists.lazarus.freepascal.org > http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus > > -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Process ID
you can can the the /proc/xxx directories to find the process with the process-ID = xxx. -Michael -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
[Lazarus] Process ID
Hi list. Which function to use in Linux (if any) to get the process ID of a running process which is not mine. GetProcessID retrieves my own process ID. I'm using OpenProcess in Win Antonio. -- ___ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
