https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=3d256e22e22d435d13cfecf39c15338cfbd6f587
commit 3d256e22e22d435d13cfecf39c15338cfbd6f587 Author: Ken Brown <[email protected]> Date: Wed Jan 27 20:06:22 2021 -0500 Cygwin: getdtablesize: always return OPEN_MAX_MAX 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. Diff: --- 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 82ddad46d..d293ff2c0 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
