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+.Dd May 20, 2024
+.Dt FORK 2
+.Os Camellia
+.Sh NAME
+.Nm fork
+.Nd copy the current process
+.Sh SYNOPSIS
+.In camellia/flags.h
+.In camellia/syscalls.h
+.In camellia/types.h
+.Ft long
+.Fo _sys_fork
+.Fa "int flags"
+.Fa "hid_t *fs_front"
+.Fc
+.Sh DESCRIPTION
+.Nm
+creates a copy of the current process and schedules it for execution.
+.Pp
+.Fa flags
+is a bitmask, with the following options:
+.Bl -tag -width FORK_SHAREHANDLE
+.It Dv FORK_SHAREMEM
+Share the parent's pagetable with the child.
+If this flag is not passed,
+the entire address space of the parent is copied (no CoW yet).
+Any new memory allocations will be reflected in both processes.
+.It Dv FORK_SHAREHANDLE
+Share the parent's handle set with the child.
+The effects of
+.Xr open 2 ,
+.Xr close 2 ,
+etc. will be reflected in both processes.
+.It Dv FORK_NOREAP
+Ignore the child in future
+.Xr wait2 2
+calls.
+It will be automatically reaped on death,
+without waiting for the parent to take action.
+.It Dv FORK_NEWFS
+Make the child responsible for a new filesystem,
+and put its corresponding handle in
+.Fa *fs_front .
+The handle can then be passed to
+.Xr mount 2 .
+.El
+.Pp
+.Fa fs_front
+is ignored,
+unless
+.Dv FORK_NEWFS
+is specified.
+It should be
+.Dv NULL
+otherwise.
+.Sh RETURN VALUES
+When successful,
+.Nm
+returns 0 in the child,
+and the child's PID in the parent.
+When not succesful, it returns one of the following (negated) errors:
+.Bl -tag -width EMFILE
+.It Er EMFILE
+.Dv FORK_NEWFS
+was specified and there's no handles left in the parent.
+.El
+.Sh SEE ALSO
+.Xr exit 2 ,
+.Xr getpid 2 ,
+.Xr getprocfs 2 ,
+.Xr wait2 2