Improve synchronization

- Fix bugs in kDos2Errno definition
- malloc() should now be thread safe
- Fix bug in rollup.com header generator
- Fix open(O_APPEND) on the New Technology
- Fix select() on the New Technology and test it
- Work towards refactoring i/o for thread safety
- Socket reads and writes on NT now poll for signals
- Work towards i/o completion ports on the New Technology
- Make read() and write() intermittently check for signals
- Blinkenlights keyboard i/o so much better on NT w/ poll()
- You can now poll() files and sockets at the same time on NT
- Fix bug in appendr() that manifests with dlmalloc footers off

libc/sysv/calls/geteuid.s

@@ -1,2 +0,0 @@
-.include "o/libc/sysv/macros.internal.inc"
-.scall geteuid,0xfff019019201906b,globl

libc/sysv/calls/recv.s

@@ -1,2 +0,0 @@
-.include "o/libc/sysv/macros.internal.inc"
-.scall recv,0xffffff066fffffff,globl

libc/sysv/calls/sendmmsg.s

@@ -1,2 +0,0 @@
-.include "o/libc/sysv/macros.internal.inc"
-.scall sendmmsg,0x1dcffffffffff133,globl

libc/sysv/calls/setgid.s

@@ -1,2 +0,0 @@
-.include "o/libc/sysv/macros.internal.inc"
-.scall setgid,0x0b50b50b520b506a,globl

libc/sysv/calls/setuid.s

@@ -1,2 +0,0 @@
-.include "o/libc/sysv/macros.internal.inc"
-.scall setuid,0x0170170172017069,globl

libc/sysv/calls/sys_epoll_create.s

@@ -1,2 +1,2 @@
 .include "o/libc/sysv/macros.internal.inc"
-.scall sys_epoll_create,0xfffffffffffff0d5,globl
+.scall sys_epoll_create,0xfffffffffffff0d5,globl,hidden

libc/sysv/calls/sys_epoll_create1.s

@@ -1,2 +1,2 @@
 .include "o/libc/sysv/macros.internal.inc"
-.scall sys_epoll_create1,0xfffffffffffff123,globl
+.scall sys_epoll_create1,0xfffffffffffff123,globl,hidden

libc/sysv/calls/sys_epoll_ctl.s

@@ -1,2 +1,2 @@
 .include "o/libc/sysv/macros.internal.inc"
-.scall sys_epoll_ctl,0xfffffffffffff0e9,globl
+.scall sys_epoll_ctl,0xfffffffffffff0e9,globl,hidden

libc/sysv/calls/sys_epoll_wait.s

@@ -1,2 +1,2 @@
 .include "o/libc/sysv/macros.internal.inc"
-.scall sys_epoll_wait,0xfffffffffffff0e8,globl
+.scall sys_epoll_wait,0xfffffffffffff0e8,globl,hidden

libc/sysv/calls/sys_geteuid.s

@@ -0,0 +1,2 @@
+.include "o/libc/sysv/macros.internal.inc"
+.scall sys_geteuid,0xfff019019201906b,globl,hidden

libc/sysv/calls/sys_mount.s

@@ -1,2 +1,2 @@
 .include "o/libc/sysv/macros.internal.inc"
-.scall sys_mount,0x19a01501520a70a5,globl
+.scall sys_mount,0x19a01501520a70a5,globl,hidden

libc/sysv/calls/sys_setgid.s

@@ -0,0 +1,2 @@
+.include "o/libc/sysv/macros.internal.inc"
+.scall sys_setgid,0x0b50b50b520b506a,globl,hidden

libc/sysv/calls/sys_setuid.s

@@ -0,0 +1,2 @@
+.include "o/libc/sysv/macros.internal.inc"
+.scall sys_setuid,0x0170170172017069,globl,hidden

libc/sysv/calls/sys_sigqueue.s

@@ -1,2 +1,2 @@
 .include "o/libc/sysv/macros.internal.inc"
-.scall sys_sigqueue,0xffffff1c8fffffff,globl
+.scall sys_sigqueue,0xffffff1c8fffffff,globl,hidden

libc/sysv/calls/sys_sigqueueinfo.s

@@ -1,2 +1,2 @@
 .include "o/libc/sysv/macros.internal.inc"
-.scall sys_sigqueueinfo,0x0f5ffffffffff081,globl
+.scall sys_sigqueueinfo,0x0f5ffffffffff081,globl,hidden

libc/sysv/calls/sys_umask.s

@@ -1,2 +1,2 @@
 .include "o/libc/sysv/macros.internal.inc"
-.scall sys_umask,0x03c03c03c203c05f,globl
+.scall sys_umask,0x03c03c03c203c05f,globl,hidden