remove incorrect usage of vfork()

From "man vfork(3)":

  The vfork() function shall be equivalent to fork(), except that the behavior
  is undefined if the process created by vfork() either modifies any data other
  than a variable of type pid_t used to store the return value from vfork(), or
  returns from the function in which vfork() was called, or calls any other
  function before successfully calling _exit() or one of the exec family of
  functions.

All of these instances do some filedescriptor modifications before calling
execve(). Since these were the only users of vfork() the tryvfork detection can
entirely go away.

CHANGES

@@ -1,4 +1,5 @@
-20190805 version: notqmail 1.07.
+201908xx version: notqmail 1.07.
+20190819 remove incorrect usage of vfork()
 20190710 code: add instchown to set ownership and mode on installed files.
 20190709 code: add instpackage to install without root access.
 20190714 code: removed idedit, install-big. var-qmail packages are no more.

Makefile

@@ -632,13 +632,6 @@ forgeries.0: \
 forgeries.7
 	nroff -man forgeries.7 > forgeries.0
 
-fork.h: \
-compile load tryvfork.c fork.h1 fork.h2
-	( ( ./compile tryvfork.c && ./load tryvfork ) >/dev/null \
-	2>&1 \
-	&& cat fork.h2 || cat fork.h1 ) > fork.h
-	rm -f tryvfork.o tryvfork
-
 forward: \
 load forward.o qmail.o strerr.a alloc.a fd.a wait.a sig.a env.a \
 substdio.a error.a str.a fs.a auto_qmail.o

TARGETS

@@ -5,7 +5,6 @@ systype
 load
 make-compile
 compile
-fork.h
 qmail-local.o
 qmail.o
 quote.o

fork.h1 → fork.h

@@ -2,6 +2,5 @@
 #define FORK_H
 
 extern int fork();
-#define vfork fork
 
 #endif

qmail-lspawn.c

@@ -156,7 +156,7 @@ char *local;
  args[0] = "bin/qmail-getpw";
  args[1] = local;
  args[2] = 0;
- switch(gpwpid = vfork())
+ switch(gpwpid = fork())
   {
    case -1:
      _exit(QLX_SYS);

qmail-rspawn.c

@@ -96,7 +96,7 @@ char *s; char *r; int at;
  args[3] = r;
  args[4] = 0;
 
- if (!(f = vfork()))
+ if (!(f = fork()))
   {
    if (fd_move(0,fdmess) == -1) _exit(111);
    if (fd_move(1,fdout) == -1) _exit(111);

qmail.c

@@ -29,7 +29,7 @@ struct qmail *qq;
   if (pipe(pim) == -1) return -1;
   if (pipe(pie) == -1) { close(pim[0]); close(pim[1]); return -1; }
 
-  switch(qq->pid = vfork()) {
+  switch(qq->pid = fork()) {
     case -1:
       close(pim[0]); close(pim[1]);
       close(pie[0]); close(pie[1]);