pdfork.2: improve markup

(cherry picked from commit cf63e3f3cd)

lib/libsys/pdfork.2

@@ -231,7 +231,7 @@ in the process specified by the
 .Fa fd
 process descriptor.
 The returned file descriptor has the
-.Va O_CLOEXEC
+.Dv O_CLOEXEC
 flag set.
 The
 .Fa flags

share/man/man4/termios.4

@@ -25,7 +25,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd January 14, 2026
+.Dd October 16, 2026
 .Dt TERMIOS 4
 .Os
 .Sh NAME
@@ -160,10 +160,11 @@ creates a new session with the
 function; other processes
 remaining in the old session that had this terminal as their controlling
 terminal continue to have it.
-A process does not relinquish its
-controlling terminal simply by closing all of its file descriptors
-associated with the controlling terminal if other processes continue to
-have it open.
+Closing all file descriptors associated with the controlling terminal in
+one process does not disassociate the terminal from the session while
+another process continues to have it open.
+When the last file descriptor associated with the controlling terminal is
+closed, the terminal is disassociated from the session.
 .Pp
 When a controlling process terminates, the controlling terminal is
 disassociated from the current session, allowing it to be acquired by a

sys/amd64/amd64/elf_machdep.c

@@ -78,9 +78,7 @@ struct sysentvec elf64_freebsd_sysvec_la48 = {
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_FREEBSD | SV_ASLR | SV_LP64 | SV_SHP |
-			    SV_TIMEKEEP | SV_RNG_SEED_VER | SV_DSO_SIG |
-			    SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_DSO_SIG | SV_LP64,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_syscallnames = syscallnames,
@@ -121,9 +119,7 @@ struct sysentvec elf64_freebsd_sysvec_la57 = {
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_FREEBSD | SV_ASLR | SV_LP64 | SV_SHP |
-			    SV_TIMEKEEP | SV_RNG_SEED_VER | SV_DSO_SIG |
-			    SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_DSO_SIG | SV_LP64,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_syscallnames = syscallnames,

sys/amd64/linux/linux_sysvec.c

@@ -700,8 +700,7 @@ struct sysentvec elf_linux_sysvec = {
 	.sv_setregs	= linux_exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_LINUX | SV_LP64 | SV_SHP | SV_SIG_DISCIGN |
-	    SV_SIG_WAITNDQ | SV_TIMEKEEP,
+	.sv_flags	= SV_ABI_LINUX_FLAGS | SV_LP64,
 	.sv_set_syscall_retval = linux_set_syscall_retval,
 	.sv_fetch_syscall_args = linux_fetch_syscall_args,
 	.sv_syscallnames = linux_syscallnames,

sys/amd64/linux32/linux32_sysvec.c

@@ -800,8 +800,7 @@ struct sysentvec elf_linux_sysvec = {
 	.sv_setregs	= linux_exec_setregs,
 	.sv_fixlimit	= linux32_fixlimit,
 	.sv_maxssiz	= &linux32_maxssiz,
-	.sv_flags	= SV_ABI_LINUX | SV_ILP32 | SV_SHP |
-	    SV_SIG_DISCIGN | SV_SIG_WAITNDQ | SV_TIMEKEEP,
+	.sv_flags	= SV_ABI_LINUX_FLAGS | SV_ILP32,
 	.sv_set_syscall_retval = linux32_set_syscall_retval,
 	.sv_fetch_syscall_args = linux32_fetch_syscall_args,
 	.sv_syscallnames = linux32_syscallnames,

sys/arm/arm/elf_machdep.c

@@ -84,9 +84,7 @@ struct sysentvec elf32_freebsd_sysvec = {
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	=
-			  SV_ASLR | SV_SHP | SV_TIMEKEEP | SV_RNG_SEED_VER |
-			  SV_ABI_FREEBSD | SV_ILP32 | SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_ILP32,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_syscallnames = syscallnames,

sys/arm64/arm64/elf_machdep.c

@@ -99,8 +99,7 @@ static struct sysentvec elf64_freebsd_sysvec = {
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_SHP | SV_TIMEKEEP | SV_ABI_FREEBSD | SV_LP64 |
-	    SV_ASLR | SV_RNG_SEED_VER | SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_LP64,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_syscallnames = syscallnames,

sys/arm64/linux/linux_sysvec.c

@@ -448,8 +448,7 @@ struct sysentvec elf_linux_sysvec = {
 	.sv_setregs	= linux_exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_LINUX | SV_LP64 | SV_SHP | SV_SIG_DISCIGN |
-	    SV_SIG_WAITNDQ | SV_TIMEKEEP,
+	.sv_flags	= SV_ABI_LINUX_FLAGS | SV_LP64,
 	.sv_set_syscall_retval = linux_set_syscall_retval,
 	.sv_fetch_syscall_args = linux_fetch_syscall_args,
 	.sv_syscallnames = linux_syscallnames,

sys/compat/ia32/ia32_sysvec.c

@@ -126,9 +126,7 @@ struct sysentvec ia32_freebsd_sysvec = {
 	.sv_setregs	= ia32_setregs,
 	.sv_fixlimit	= ia32_fixlimit,
 	.sv_maxssiz	= &ia32_maxssiz,
-	.sv_flags	= SV_ABI_FREEBSD | SV_ASLR | SV_ILP32 |
-			    SV_SHP | SV_TIMEKEEP | SV_RNG_SEED_VER |
-			    SV_DSO_SIG | SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_DSO_SIG | SV_ILP32,
 	.sv_set_syscall_retval = ia32_set_syscall_retval,
 	.sv_fetch_syscall_args = ia32_fetch_syscall_args,
 	.sv_syscallnames = freebsd32_syscallnames,

sys/fs/devfs/devfs_vnops.c

@@ -59,6 +59,7 @@
 #include <sys/stat.h>
 #include <sys/sx.h>
 #include <sys/sysctl.h>
+#include <sys/sysent.h>
 #include <sys/time.h>
 #include <sys/ttycom.h>
 #include <sys/unistd.h>
@@ -716,8 +717,13 @@ devfs_close(struct vop_close_args *ap)
 	 * process' controlling terminal.  In that case,
 	 * if the reference count is 2 (this last descriptor
 	 * plus the session), release the reference from the session.
+	 *
+	 * Some ABIs keep the controlling terminal after the last
+	 * slave descriptor is closed.  A closer with SV_PERSISTENT_CTTY
+	 * leaves the session reference in place.
 	 */
-	if (de->de_usecount == 2 && td != NULL) {
+	if (!SV_PROC_FLAG(curproc, SV_PERSISTENT_CTTY) &&
+	    de->de_usecount == 2 && td != NULL) {
 		p = td->td_proc;
 		PROC_LOCK(p);
 		if (vp == p->p_session->s_ttyvp) {

sys/i386/i386/elf_machdep.c

@@ -74,8 +74,7 @@ struct sysentvec elf32_freebsd_sysvec = {
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_FREEBSD | SV_ASLR | SV_ILP32 |
-			    SV_SHP | SV_TIMEKEEP | SV_RNG_SEED_VER | SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_ILP32,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_syscallnames = syscallnames,

sys/i386/linux/linux_sysvec.c

@@ -597,7 +597,7 @@ struct sysentvec linux_sysvec = {
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
 	.sv_flags	= SV_ABI_LINUX | SV_AOUT | SV_ILP32 |
-	    SV_SIG_DISCIGN | SV_SIG_WAITNDQ,
+	    SV_SIG_DISCIGN | SV_SIG_WAITNDQ | SV_PERSISTENT_CTTY,
 	.sv_set_syscall_retval = linux_set_syscall_retval,
 	.sv_fetch_syscall_args = linux_fetch_syscall_args,
 	.sv_syscallnames = linux_syscallnames,
@@ -640,8 +640,7 @@ struct sysentvec elf_linux_sysvec = {
 	.sv_setregs	= linux_exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_LINUX | SV_ILP32 | SV_SHP |
-	    SV_SIG_DISCIGN | SV_SIG_WAITNDQ | SV_TIMEKEEP,
+	.sv_flags	= SV_ABI_LINUX_FLAGS | SV_ILP32,
 	.sv_set_syscall_retval = linux_set_syscall_retval,
 	.sv_fetch_syscall_args = linux_fetch_syscall_args,
 	.sv_syscallnames = NULL,

sys/powerpc/powerpc/elf32_machdep.c

@@ -123,8 +123,7 @@ struct sysentvec elf32_freebsd_sysvec = {
 	.sv_fixlimit	= NULL,
 #endif
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_FREEBSD | SV_ILP32 | SV_SHP | SV_ASLR |
-			    SV_TIMEKEEP | SV_RNG_SEED_VER | SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_ILP32,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_shared_page_base = FREEBSD32_SHAREDPAGE,

sys/powerpc/powerpc/elf64_machdep.c

@@ -85,8 +85,7 @@ struct sysentvec elf64_freebsd_sysvec_v1 = {
 	.sv_setregs	= exec_setregs_funcdesc,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_FREEBSD | SV_LP64 | SV_SHP | SV_ASLR |
-			    SV_TIMEKEEP | SV_RNG_SEED_VER | SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_LP64,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_syscallnames = syscallnames,
@@ -129,8 +128,7 @@ struct sysentvec elf64_freebsd_sysvec_v2 = {
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_FREEBSD | SV_LP64 | SV_SHP | SV_ASLR |
-			    SV_TIMEKEEP | SV_RNG_SEED_VER | SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_LP64,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_syscallnames = syscallnames,

sys/riscv/riscv/elf_machdep.c

@@ -82,8 +82,7 @@ static struct sysentvec elf64_freebsd_sysvec = {
 	.sv_setregs	= exec_setregs,
 	.sv_fixlimit	= NULL,
 	.sv_maxssiz	= NULL,
-	.sv_flags	= SV_ABI_FREEBSD | SV_LP64 | SV_SHP | SV_TIMEKEEP |
-	    SV_ASLR | SV_RNG_SEED_VER | SV_SIGSYS,
+	.sv_flags	= SV_ABI_FREEBSD_FLAGS | SV_LP64,
 	.sv_set_syscall_retval = cpu_set_syscall_retval,
 	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
 	.sv_syscallnames = syscallnames,

sys/sys/sysent.h

@@ -163,18 +163,19 @@ struct sysentvec {
 	struct regset	**sv_regset_end;
 };
 
-#define	SV_ILP32	0x000100	/* 32-bit executable. */
-#define	SV_LP64		0x000200	/* 64-bit executable. */
-#define	SV_RESERVED0	0x004000	/* Formerly SV_IA32 */
-#define	SV_AOUT		0x008000	/* a.out executable. */
-#define	SV_SHP		0x010000	/* Shared page. */
-#define	SV_SIGSYS	0x020000	/* SIGSYS for non-existing syscall */
-#define	SV_TIMEKEEP	0x040000	/* Shared page timehands. */
-#define	SV_ASLR		0x080000	/* ASLR allowed. */
-#define	SV_RNG_SEED_VER	0x100000	/* random(4) reseed generation. */
-#define	SV_SIG_DISCIGN	0x200000	/* Do not discard ignored signals */
-#define	SV_SIG_WAITNDQ	0x400000	/* Wait does not dequeue SIGCHLD */
-#define	SV_DSO_SIG	0x800000	/* Signal trampoline packed in dso */
+#define	SV_ILP32	0x00000100	/* 32-bit executable. */
+#define	SV_LP64		0x00000200	/* 64-bit executable. */
+#define	SV_RESERVED0	0x00004000	/* Formerly SV_IA32 */
+#define	SV_AOUT		0x00008000	/* a.out executable. */
+#define	SV_SHP		0x00010000	/* Shared page. */
+#define	SV_SIGSYS	0x00020000	/* SIGSYS for non-existing syscall */
+#define	SV_TIMEKEEP	0x00040000	/* Shared page timehands. */
+#define	SV_ASLR		0x00080000	/* ASLR allowed. */
+#define	SV_RNG_SEED_VER	0x00100000	/* random(4) reseed generation. */
+#define	SV_SIG_DISCIGN	0x00200000	/* Do not discard ignored signals */
+#define	SV_SIG_WAITNDQ	0x00400000	/* Wait does not dequeue SIGCHLD */
+#define	SV_DSO_SIG	0x00800000	/* Signal trampoline packed in dso */
+#define	SV_PERSISTENT_CTTY 0x01000000 /* Keep ctty after the last close */
 
 #define	SV_ABI_MASK	0xff
 #define	SV_PROC_FLAG(p, x)	((p)->p_sysent->sv_flags & (x))
@@ -186,6 +187,11 @@ struct sysentvec {
 #define	SV_ABI_FREEBSD 	9
 #define	SV_ABI_UNDEF	255
 
+#define	SV_ABI_FREEBSD_FLAGS	(SV_ABI_FREEBSD | SV_ASLR | SV_SHP | \
+    SV_TIMEKEEP | SV_RNG_SEED_VER | SV_SIGSYS)
+#define	SV_ABI_LINUX_FLAGS	(SV_ABI_LINUX | SV_SHP | SV_SIG_DISCIGN | \
+    SV_SIG_WAITNDQ | SV_TIMEKEEP | SV_PERSISTENT_CTTY)
+
 /* sv_coredump flags */
 #define	SVC_PT_COREDUMP	0x00000001	/* dump requested by ptrace(2) */
 #define	SVC_NOCOMPRESS	0x00000002	/* disable compression. */