Re: Is UNIX home directory really needed to run root? (fwd)

Hi Dimitri,

   a priory the HOME directory is not needed anymore. Before removing the Fatal() I've to check carefully if all occasions where we use the HomeDirectory is properly protected against no-home directory.

Cheers, Fons.

>
> ---------- Forwarded message ----------
> Date: Fri, 24 Aug 2007 20:19:32 -0400
> From: Dimitri Bourilkov <bourilkov_at_phys.ufl.edu>
> To: roottalk_at_pcroot.cern.ch
> Subject: [ROOT] Is UNIX home directory really needed to run root?
>
> Hi,
>
> Having succeeded to use condor flocking to submit (my) batch jobs, I
> am trying to submit _root_ batch jobs (root -b -q xxx.C) to a remote
> farm where I do not have a unix account (condor is taking care of this),
> just an NFS mounted working space. The jobs are running into problems,
> terminating with the message:
>
> Fatal in <TROOT::InitSystem>: HOME directory not set
>
> Looking in the root source this comes from the snippets enclosed below.
> If I read them correctly, things are more or less hardcoded to look for
> the unix user and get the home dir from the passwd file.
>
> My questions are:
> 1) Is this really needed to run root?
> 2) Or defining a dir where root can read/write could be enough, and
> how to achieve this (if needed, modifying the code)?
>
> Thanks, Dimitri
>
> PS Actually if mydir[kMAXPATHLEN] is initialized before calling
> TUnixSystem::UnixHomedirectory maybe things will behave differently, is
> this feasible and a viable solution?
>
> ============================
> void TROOT::InitSystem()
> {
> // Initialize operating system interface.
>
> if (gSystem == 0) {
> #if defined(R__UNIX)
> gSystem = new TUnixSystem;
> #elif defined(R__WIN32)
> gSystem = new TWinNTSystem;
> #elif defined(R__VMS)
> gSystem = new TVmsSystem;
> #else
> gSystem = new TSystem;
> #endif
>
> if (gSystem->Init())
> fprintf(stderr, "Fatal in <TROOT::InitSystem>: can't init
> operating system layer\n");
>
> if (!gSystem->HomeDirectory())
> fprintf(stderr, "Fatal in <TROOT::InitSystem>: HOME directory
> not set\n");
> .....
>
> ===============================
> and in TUnixSystem
> ===============================
> //______________________________________________________________________________
>
> const char *TUnixSystem::HomeDirectory(const char *userName)
> {
> // Return the user's home directory.
>
> return UnixHomedirectory(userName);
> }
>
> //---- directories
> -------------------------------------------------------------
>
> //______________________________________________________________________________
>
> const char *TUnixSystem::UnixHomedirectory(const char *name)
> {
> // Returns the user's home directory.
>
> static char path[kMAXPATHLEN], mydir[kMAXPATHLEN];
> struct passwd *pw;
>
> if (name) {
> pw = getpwnam(name);
> if (pw) {
> strncpy(path, pw->pw_dir, kMAXPATHLEN);
> return path;
> }
> } else {
> if (mydir[0])
> return mydir;
> pw = getpwuid(getuid());
> if (pw) {
> strncpy(mydir, pw->pw_dir, kMAXPATHLEN);
> return mydir;
> }
> }
> return 0;
> }
>

-- 
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