Re: ulimit -a: -r vs -N [was Re: pkgsrc patches for zsh]

[Peter Stephenson <p.stephenson@xxxxxxxxxxx>]

On Wed, 25 Jun 2014 10:36:55 +0200
Thomas Klausner <tk@xxxxxxxxxx> wrote:
> The description for -T is not correct for NetBSD though. (I don't know
> how this limit works on other operating systems.)
> From NetBSD's sh(1)'s ulimit section:
> 
>  -r          show or set the limit on the number of threads this
>              user can have at one time
> 
> So the limit is not per-process, but for the user in total.

That's basically how -T is documented in the zsh manual, so it may be
the description of -T from ulimit that's wrong.  If anyone can confirm
(Linux doesn't have either, it looks like NPROC is the nearest), I will
change this globally, but for now it's just for NetBSD.

I've added compatibility with sh when NTHR is present and RTPRIO isn't
--- which should be just about specific enough that the additional
compatibility more than offsets any confusion.

> The check for RLIMIT_NTHR is already in that file, about 10 lines
> higher.

Thanks, should have spotted that.

diff --git a/Doc/Zsh/builtins.yo b/Doc/Zsh/builtins.yo
index 9905ab5..dd090d6 100644
--- a/Doc/Zsh/builtins.yo
+++ b/Doc/Zsh/builtins.yo
@@ -1940,6 +1940,9 @@ sitem(tt(-m))(Kilobytes on the size of physical memory.)
 sitem(tt(-n))(open file descriptors.)
 sitem(tt(-p))(The number of pseudo-terminals.)
 sitem(tt(-q))(Bytes in POSIX message queues.)
+sitem(tt(-r))(Maximum real time priority.  On some systems where this
+is not available, such as NetBSD, this has the same effect as tt(-T)
+for compatibility with tt(sh).)
 sitem(tt(-s))(Kilobytes on the size of the stack.)
 sitem(tt(-T))(The number of simultaneous threads available to the user.)
 sitem(tt(-t))(CPU seconds to be used.)
diff --git a/Src/Builtins/rlimits.c b/Src/Builtins/rlimits.c
index 0bcafda..bcf9ad8 100644
--- a/Src/Builtins/rlimits.c
+++ b/Src/Builtins/rlimits.c
@@ -32,12 +32,17 @@
 
 #if defined(HAVE_GETRLIMIT) && defined(RLIM_INFINITY)
 
-#ifdef RLIMIT_POSIXLOCKS
+#if defined(HAVE_RLIMIT_POSIXLOCKS) && !defined(HAVE_RLIMIT_LOCKS)
 #  define RLIMIT_LOCKS		RLIMIT_POSIXLOCKS
+#  define HAVE_RLIMIT_LOCKS     1
 #endif
 
-#ifdef RLIMIT_NTHR
+#if defined(HAVE_RLIMIT_NTHR) && !defined(HAVE_RLIMIT_PTHREAD)
 #  define RLIMIT_PTHREAD	RLIMIT_NTHR
+#  define HAVE_RLIMIT_PTHREAD   1
+#  define THREAD_FMT            "-T: threads                         "
+#else
+#  define THREAD_FMT            "-T: threads per process             "
 #endif
 
 enum {
@@ -373,7 +378,7 @@ printulimit(char *nam, int lim, int hard, int head)
 # ifdef HAVE_RLIMIT_PTHREAD
     case RLIMIT_PTHREAD:
 	if (head)
-	    printf("-T: threads per process             ");
+	    printf(THREAD_FMT);
 	break;
 # endif /* HAVE_RLIMIT_PTHREAD */
 # ifdef HAVE_RLIMIT_NICE
@@ -387,6 +392,14 @@ printulimit(char *nam, int lim, int hard, int head)
 	if (head)
 	    printf("-r: max rt priority                 ");
 	break;
+# else
+#  ifdef HAVE_RLIMIT_NTHR
+	/* For compatibility with sh on NetBSD */
+    case RLIMIT_NTHR:
+	if (head)
+	    printf("-r: threads                         ");
+	break;
+#  endif /* HAVE_RLIMIT_NTHR */
 # endif /* HAVE_RLIMIT_RTPRIO */
 # ifdef HAVE_RLIMIT_NPTS
     case RLIMIT_NPTS:
@@ -860,6 +873,13 @@ bin_ulimit(char *name, char **argv, UNUSED(Options ops), UNUSED(int func))
 		case 'r':
 		    res = RLIMIT_RTPRIO;
 		    break;
+# else
+#  ifdef HAVE_RLIMIT_NTHR
+		    /* For compatibility with sh on NetBSD */
+		case 'r':
+		    res = RLIMIT_NTHR;
+		    break;
+#  endif /* HAVE_RLIMIT_NTHR */
 # endif
 # ifdef HAVE_RLIMIT_NPTS
 		case 'p':
@@ -876,6 +896,11 @@ bin_ulimit(char *name, char **argv, UNUSED(Options ops), UNUSED(int func))
 		    res = RLIMIT_KQUEUES;
 		    break;
 # endif
+# ifdef HAVE_RLIMIT_PTHREAD
+		case 'T':
+		    res = RLIMIT_PTHREAD;
+		    break;
+# endif
 		default:
 		    /* unrecognised limit */
 		    zwarnnam(name, "bad option: -%c", *options);


-- 
Peter Stephenson <p.stephenson@xxxxxxxxxxx>  Principal Software Engineer
Tel: +44 (0)1223 434724                Samsung Cambridge Solution Centre
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