Fix i686 fork.

redox-rt/src/arch/i686.rs

@@ -5,6 +5,7 @@ use syscall::*;
 use crate::{
     proc::{fork_inner, FdGuard},
     signal::{inner_fastcall, RtSigarea, SigStack, PROC_CONTROL_STRUCT},
+    RtTcb,
 };
 
 // Setup a stack starting from the very end of the address space, and then growing downwards.
@@ -80,7 +81,11 @@ unsafe extern "cdecl" fn fork_impl(initial_rsp: *mut usize) -> usize {
 
 unsafe extern "cdecl" fn child_hook(cur_filetable_fd: usize, new_pid_fd: usize) {
     let _ = syscall::close(cur_filetable_fd);
-    let _ = syscall::close(new_pid_fd);
+    // TODO: Currently pidfd == threadfd, but this will not be the case later.
+    RtTcb::current()
+        .thr_fd
+        .get()
+        .write(Some(FdGuard::new(new_pid_fd)));
 }
 
 asmfunction!(__relibc_internal_fork_wrapper -> usize: ["

redox-rt/src/arch/x86_64.rs

@@ -91,7 +91,7 @@ unsafe extern "sysv64" fn fork_impl(initial_rsp: *mut usize) -> usize {
 
 unsafe extern "sysv64" fn child_hook(cur_filetable_fd: usize, new_pid_fd: usize) {
     let _ = syscall::close(cur_filetable_fd);
-    // TODO: Currently equivalent, but this will not be the case later.
+    // TODO: Currently pidfd == threadfd, but this will not be the case later.
     RtTcb::current()
         .thr_fd
         .get()

redox-rt/src/signal.rs

@@ -481,7 +481,7 @@ pub fn setup_sighandler(tcb: &RtTcb) {
         arch.altstack_top = usize::MAX;
         arch.altstack_bottom = 0;
         // TODO
-        #[cfg(any(target_arch = "i686", target_arch = "aarch64"))]
+        #[cfg(any(target_arch = "x86", target_arch = "aarch64"))]
         {
             arch.pctl = core::ptr::addr_of!(PROC_CONTROL_STRUCT) as usize;
         }