From 4bd026cccb2c22279dd9c88e704642c5a65d3c53 Mon Sep 17 00:00:00 2001 From: Michael Santos Date: Fri, 30 Apr 2010 12:22:11 -0400 Subject: Support opening files in exclusive mode Add an option that atomically tests for the existence of a file and creates it if the file does not exist, by passing the O_EXCL flag to open() on Unix and CREATE_NEW flag on Windows. Support for O_EXCL varies across platforms and filesystems. {ok, Fd} = file:open("/tmp/foo", [write,exclusive]), {error, eexist} = file:open("/tmp/foo", [write,exclusive]). --- erts/emulator/drivers/unix/unix_efile.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'erts/emulator/drivers/unix') diff --git a/erts/emulator/drivers/unix/unix_efile.c b/erts/emulator/drivers/unix/unix_efile.c index ea016526ef..0052ac0739 100644 --- a/erts/emulator/drivers/unix/unix_efile.c +++ b/erts/emulator/drivers/unix/unix_efile.c @@ -706,6 +706,9 @@ efile_openfile(Efile_error* errInfo, /* Where to return error codes. */ #endif } + if (flags & EFILE_MODE_EXCL) { + mode |= O_EXCL; + } #ifdef VXWORKS if (*name != '/') { -- cgit v1.2.3