7 files changed, 38 insertions, 20 deletions
diff --git a/otherlibs/unix/connect.c b/otherlibs/unix/connect.c
index 66f20ae66..b69396b4b 100644
--- a/otherlibs/unix/connect.c
+++ b/otherlibs/unix/connect.c
@@ -21,9 +21,12 @@
 value unix_connect(socket, address)   /* ML */
      value socket, address;
 {
+  int retcode;
   get_sockaddr(address);
-  if (connect(Int_val(socket), &sock_addr.s_gen, sock_addr_len) == -1)
-    uerror("connect", Nothing);
+  enter_blocking_section();
+  retcode = connect(Int_val(socket), &sock_addr.s_gen, sock_addr_len);
+  leave_blocking_section();
+  if (retcode == -1) uerror("connect", Nothing);
   return Val_unit;
 }
 
diff --git a/otherlibs/unix/gethost.c b/otherlibs/unix/gethost.c
index 999cdc2ca..a634d2a43 100644
--- a/otherlibs/unix/gethost.c
+++ b/otherlibs/unix/gethost.c
@@ -61,8 +61,12 @@ static value alloc_host_entry(entry)
 value unix_gethostbyaddr(a)   /* ML */
      value a;
 {
+  uint32 addr;
   struct hostent * entry;
-  entry = gethostbyaddr((char *) &GET_INET_ADDR(a), 4, AF_INET);
+  addr = GET_INET_ADDR(a);
+  enter_blocking_section();
+  entry = gethostbyaddr((char *) &addr, 4, AF_INET);
+  leave_blocking_section();
   if (entry == (struct hostent *) NULL) raise_not_found();
   return alloc_host_entry(entry);
 }
@@ -70,8 +74,13 @@ value unix_gethostbyaddr(a)   /* ML */
 value unix_gethostbyname(name)   /* ML */
      value name;
 {
+  char hostname[256];
   struct hostent * entry;
-  entry = gethostbyname(String_val(name));
+  strncpy(hostname, String_val(name), sizeof(hostname) - 1);
+  hostname[sizeof(hostname) - 1] = 0;
+  enter_blocking_section();
+  entry = gethostbyname(hostname);
+  leave_blocking_section();
   if (entry == (struct hostent *) NULL) raise_not_found();
   return alloc_host_entry(entry);
 }
diff --git a/otherlibs/unix/read.c b/otherlibs/unix/read.c
index 49485ce43..f7870a821 100644
--- a/otherlibs/unix/read.c
+++ b/otherlibs/unix/read.c
@@ -18,6 +18,7 @@ value unix_read(fd, buf, ofs, len) /* ML */
      value fd, buf, ofs, len;
 {
   int ret;
+  buf = unix_freeze_buffer(buf);
   enter_blocking_section();
   ret = read(Int_val(fd), &Byte(buf, Long_val(ofs)), Int_val(len));
   leave_blocking_section();
diff --git a/otherlibs/unix/sendrecv.c b/otherlibs/unix/sendrecv.c
index dfa54c902..8b9f7452a 100644
--- a/otherlibs/unix/sendrecv.c
+++ b/otherlibs/unix/sendrecv.c
@@ -30,6 +30,7 @@ value unix_recv(sock, buff, ofs, len, flags) /* ML */
      value sock, buff, ofs, len, flags;
 {
   int ret;
+  buff = unix_freeze_buffer(buff);
   enter_blocking_section();
   ret = recv(Int_val(sock), &Byte(buff, Long_val(ofs)), Int_val(len),
              convert_flag_list(flags, msg_flag_table));
@@ -45,6 +46,7 @@ value unix_recvfrom(sock, buff, ofs, len, flags) /* ML */
   value res;
   Push_roots(a, 1);
 
+  buff = unix_freeze_buffer(buff);
   sock_addr_len = sizeof(sock_addr);
   enter_blocking_section();
   retcode = recvfrom(Int_val(sock), &Byte(buff, Long_val(ofs)), Int_val(len),
@@ -64,6 +66,7 @@ value unix_send(sock, buff, ofs, len, flags) /* ML */
      value sock, buff, ofs, len, flags;
 {
   int ret;
+  buff = unix_freeze_buffer(buff);
   enter_blocking_section();
   ret = send(Int_val(sock), &Byte(buff, Long_val(ofs)), Int_val(len),
              convert_flag_list(flags, msg_flag_table));
@@ -77,6 +80,7 @@ value unix_sendto_native(sock, buff, ofs, len, flags, dest)
 {
   int ret;
   get_sockaddr(dest);
+  buff = unix_freeze_buffer(buff);
   enter_blocking_section();
   ret = sendto(Int_val(sock), &Byte(buff, Long_val(ofs)),
                Int_val(len), convert_flag_list(flags, msg_flag_table),
diff --git a/otherlibs/unix/unix.h b/otherlibs/unix/unix.h
index 5a26a7c3d..8783328f8 100644
--- a/otherlibs/unix/unix.h
+++ b/otherlibs/unix/unix.h
@@ -13,19 +13,6 @@
 
 #define Nothing ((value) 0)
 
-#ifndef NULL
-#ifdef __STDC__
-#define NULL ((void *) 0)
-#else
-#define NULL ((char *) 0)
-#endif
-#endif
-
-#ifdef __STDC__
-extern void unix_error(int errcode, char * cmdname, value arg);
-extern void uerror(char * cmdname, value arg);
-#else
-void unix_error();
-void uerror();
-#endif
-
+extern void unix_error P((int errcode, char * cmdname, value arg));
+extern void uerror P((char * cmdname, value arg));
+extern value unix_freeze_buffer P((value));
diff --git a/otherlibs/unix/unixsupport.c b/otherlibs/unix/unixsupport.c
index 2f79f906f..08942454b 100644
--- a/otherlibs/unix/unixsupport.c
+++ b/otherlibs/unix/unixsupport.c
@@ -298,3 +298,16 @@ void uerror(cmdname, cmdarg)
 {
   unix_error(errno, cmdname, cmdarg);
 }
+
+value unix_freeze_buffer(buf)
+     value buf;
+{
+  if (Is_young(buf)) {
+    Push_roots(r, 1);
+    r[0] = buf;
+    minor_collection();
+    buf = r[0];
+    Pop_roots();
+  }
+  return buf;
+}
diff --git a/otherlibs/unix/write.c b/otherlibs/unix/write.c
index 99ab72131..db7ab276c 100644
--- a/otherlibs/unix/write.c
+++ b/otherlibs/unix/write.c
@@ -18,6 +18,7 @@ value unix_write(fd, buf, ofs, len) /* ML */
      value fd, buf, ofs, len;
 {
   int ret;
+  buf = unix_freeze_buffer(buf);
   enter_blocking_section();
   ret = write(Int_val(fd), &Byte(buf, Long_val(ofs)), Int_val(len));
   leave_blocking_section();