From: Ken Brown <kbrown@cornell.edu>
To: cygwin-patches@cygwin.com
Subject: [PATCH] Cygwin: getdtablesize: always return OPEN_MAX_MAX
Date: Wed, 27 Jan 2021 21:51:50 -0500 [thread overview]
Message-ID: <20210128025150.46708-1-kbrown@cornell.edu> (raw)
According to the Linux man page for getdtablesize(3), the latter is
supposed to return "the maximum number of files a process can have
open, one more than the largest possible value for a file descriptor."
The constant OPEN_MAX_MAX is the only limit enforced by Cygwin, so we
now return that.
Previously getdtablesize returned the current size of cygheap->fdtab,
Cygwin's internal file descriptor table. But this is a dynamically
growing table, and its current size does not reflect an actual limit
on the number of open files.
With this change, gnulib now reports that getdtablesize and
fcntl(F_DUPFD) work on Cygwin. Packages like GNU tar that use the
corresponding gnulib modules will no longer use gnulib replacements on
Cygwin.
---
winsup/cygwin/syscalls.cc | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index 5da05b18a..1f16d54b9 100644
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -2887,7 +2887,7 @@ setdtablesize (int size)
extern "C" int
getdtablesize ()
{
- return cygheap->fdtab.size;
+ return OPEN_MAX_MAX;
}
extern "C" int
--
2.30.0
next reply other threads:[~2021-01-28 2:52 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-28 2:51 Ken Brown [this message]
2021-01-28 10:20 ` Corinna Vinschen
2021-01-28 13:42 ` Ken Brown
2021-01-28 16:07 ` Corinna Vinschen
2021-01-28 16:13 ` Corinna Vinschen
2021-01-28 22:28 ` Ken Brown
2021-01-29 19:23 ` Ken Brown
2021-02-01 9:42 ` Corinna Vinschen
2021-01-28 20:33 ` Ken Brown
2021-02-01 9:50 ` Corinna Vinschen
2021-02-01 10:46 ` Corinna Vinschen
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