Merge branch 'egil/fix-compiler-warning/OTP-9542' into dev

* egil/fix-compiler-warning/OTP-9542:
  gs: Update to modern type guards in examples
  os_mon: Check results from fgets in cpu_sup
  erts: Remove compiler warning in sys.c

7 files changed, 32 insertions, 21 deletions

diff --git a/erts/emulator/sys/unix/sys.c b/erts/emulator/sys/unix/sys.c
index cc08c1d20a..e5ee0df7fa 100644
--- a/erts/emulator/sys/unix/sys.c
+++ b/erts/emulator/sys/unix/sys.c
@@ -3087,10 +3087,10 @@ get_value(char* rest, char** argv, int* ip)
 void
 erl_sys_args(int* argc, char** argv)
 {
-    erts_smp_rwmtx_init(&environ_rwmtx, "environ");
-
     int i, j;
 
+    erts_smp_rwmtx_init(&environ_rwmtx, "environ");
+
     i = 1;
 
     ASSERT(argc && argv);
diff --git a/lib/gs/contribs/bonk/sounder.erl b/lib/gs/contribs/bonk/sounder.erl
index 11ab03d167..899f20d4e0 100644
--- a/lib/gs/contribs/bonk/sounder.erl
+++ b/lib/gs/contribs/bonk/sounder.erl
@@ -72,13 +72,13 @@ stop() ->
     sounder ! {stop},
     ok end.
 
-new(File) when list(File) -> new(list_to_atom(File));
-new(File) when atom(File) ->
+new(File) when is_list(File) -> new(list_to_atom(File));
+new(File) when is_atom(File) ->
     catch begin check(),
     sounder ! {new,File,self()},
     wait_for_ack(sounder) end.
 
-play(No) when integer(No) ->
+play(No) when is_integer(No) ->
     catch begin check(),
     sounder ! {play, No, self()},
     wait_for_ack(sounder) end.
@@ -94,14 +94,14 @@ go()  ->
 
 loop(Port) ->
     receive
-	{new, File, From} when atom(File) ->
+	{new, File, From} when is_atom(File) ->
 	    Port ! {self(),{command,lists:append([0],atom_to_list(File))}},
 	    From ! {sounder,wait_for_ack(Port)},
 	    loop(Port);
 	{play,silent,From} ->
 	    From ! {sounder,false},
 	    loop(Port);
-	{play,No,From} when integer(No) ->
+	{play,No,From} when is_integer(No) ->
 	    Port ! {self(),{command,[No]}},
 	    From ! {sounder,wait_for_ack(Port)},
 	    loop(Port);
@@ -118,13 +118,13 @@ loop(Port) ->
 
 nosound() ->
     receive
-	{new,File,From} when atom(File) ->
+	{new,File,From} when is_atom(File) ->
 	    From ! {sounder,{ok,silent}},
 	    nosound();
 	{play,silent,From} ->
 	    From ! {sounder,true},
 	    nosound();
-	{play,No,From} when integer(No) ->
+	{play,No,From} when is_integer(No) ->
 	    From ! {sounder,{error,no_audio_cap}},
 	    nosound();
 	{stop} ->
@@ -135,7 +135,7 @@ nosound() ->
 
 wait_for_ack(sounder) ->
     receive {sounder,Res} -> Res end;
-wait_for_ack(Port) when port(Port) ->
+wait_for_ack(Port) when is_port(Port) ->
     receive
 	{Port,{data,"ok"}} ->
 	    ok;
@@ -149,7 +149,7 @@ wait_for_ack(Port) when port(Port) ->
 
 check() ->
     case whereis(sounder) of
-	Pid when pid(Pid) -> 
+	Pid when is_pid(Pid) -> 
 	    ok;
 	undefined ->
 	    throw({error,sounder_not_started})
diff --git a/lib/gs/contribs/cols/cols.erl b/lib/gs/contribs/cols/cols.erl
index 67b46d0dfb..439eb717f7 100644
--- a/lib/gs/contribs/cols/cols.erl
+++ b/lib/gs/contribs/cols/cols.erl
@@ -278,7 +278,7 @@ fall_column([], _X, _Y, ColumnAcc, ChecksAcc) ->
 fall_column([black|Colors], X, Y, ColumnAcc, ChecksAcc) ->
     case find_box(Colors) of
 	false -> {ColumnAcc, ChecksAcc};
-	NewColors when list(NewColors) ->
+	NewColors when is_list(NewColors) ->
 		fall_one_step(NewColors, X, Y, ColumnAcc, ChecksAcc)
     end;
 fall_column([Color|Colors], X, Y, ColumnAcc, ChecksAcc) ->
@@ -330,7 +330,7 @@ new_column_list([], _, _) -> [].
 %%----------------------------------------------------------------------
 %% Returns: a reversed list of colors.
 %%----------------------------------------------------------------------
-columntuple_to_list(ColumnTuple) when tuple(ColumnTuple) ->
+columntuple_to_list(ColumnTuple) when is_tuple(ColumnTuple) ->
     columntuple_to_list(tuple_to_list(ColumnTuple),[]).
 
 columntuple_to_list([],Acc) -> Acc;
diff --git a/lib/gs/contribs/mandel/mandel.erl b/lib/gs/contribs/mandel/mandel.erl
index d4d2452463..579f8e487b 100644
--- a/lib/gs/contribs/mandel/mandel.erl
+++ b/lib/gs/contribs/mandel/mandel.erl
@@ -119,7 +119,7 @@ start_client(Opts,Nodes) ->
 
 try_random(random,Low,High) ->
     random:uniform()*(High-Low)+Low;
-try_random(Float,_Low,_High) when number(Float) -> Float.
+try_random(Float,_Low,_High) when is_number(Float) -> Float.
     
 
 %%-----------------------------------------------------------------
diff --git a/lib/gs/contribs/othello/othello_board.erl b/lib/gs/contribs/othello/othello_board.erl
index 0206ba2ded..6ccb79b7e4 100644
--- a/lib/gs/contribs/othello/othello_board.erl
+++ b/lib/gs/contribs/othello/othello_board.erl
@@ -147,7 +147,7 @@ but_pressed("Help",_ButtId,_User,GamePid,_Shell,_Wids,_Op) ->
 but_pressed("Newgame",_ButtId,_User,GamePid,_Shell,Wids,Options) ->
     new_game(GamePid,Wids,Options);
 but_pressed([],ButtId,User,GamePid,_Shell,_Wids,_Op) 
-					when pid(GamePid),User == player ->
+					when is_pid(GamePid),User == player ->
     [C,R] = atom_to_list(ButtId),
     GamePid ! {self(),position,othello_adt:pos(C-96,translate(R-48))},
     GamePid;
@@ -243,7 +243,7 @@ game_msg(Msg,User,GamePid,Shell,Wids,Options) ->
     end.
     
 
-new_game(GamePid,Wids,Options) when pid(GamePid) ->
+new_game(GamePid,Wids,Options) when is_pid(GamePid) ->
     exit(GamePid,kill),
     new_game(Wids,Options);
 new_game(_,Wids,Options) ->
diff --git a/lib/gs/examples/calc2.erl b/lib/gs/examples/calc2.erl
index d28780de01..9969a6c40f 100644
--- a/lib/gs/examples/calc2.erl
+++ b/lib/gs/examples/calc2.erl
@@ -54,7 +54,7 @@ calc() ->
 
 calc_loop(Lbl,M,V,Op) ->
     receive
-	{gs,_,click,D,_} when integer(D) -> 
+	{gs,_,click,D,_} when is_integer(D) -> 
 	    digit_press(Lbl,M,V*10+D,Op);
 	{gs,_,click,'C',_} -> 
 	    c(Lbl,M,V,Op);
diff --git a/lib/os_mon/c_src/cpu_sup.c b/lib/os_mon/c_src/cpu_sup.c
index fbf318c614..e3bdbd1489 100644
--- a/lib/os_mon/c_src/cpu_sup.c
+++ b/lib/os_mon/c_src/cpu_sup.c
@@ -191,7 +191,10 @@ int main(int argc, char** argv) {
 static cpu_t *read_procstat(FILE *fp, cpu_t *cpu) {
     char buffer[BUFFERSIZE];
 
-    fgets(buffer, BUFFERSIZE, fp);
+    if (fgets(buffer, BUFFERSIZE, fp) == NULL) {
+	memset(cpu, 0, sizeof(cpu_t));
+	return cpu;
+    }
     sscanf(buffer, "cpu%u %Lu %Lu %Lu %Lu %Lu %Lu %Lu %Lu",
 	&(cpu->id),
 	&(cpu->user),
@@ -223,7 +226,11 @@ static void util_measure(unsigned int **result_vec, int *result_sz) {
 	return;
     }
 
-    fgets(buffer, BUFFERSIZE, fp); /*ignore read*/
+	/*ignore read*/
+    if (fgets(buffer, BUFFERSIZE, fp) == NULL) {
+	*result_sz = 0;
+	return;
+    }
     rv = *result_vec; 
     rv[0] = no_of_cpus;
     rv[1] = CU_VALUES;
@@ -447,8 +454,12 @@ static void sendv(unsigned int data[], int ints) {
 }
 
 static void error(char* err_msg) {
-  write(FD_ERR, err_msg, strlen(err_msg));
-  write(FD_ERR, "\n", 1);
+  /* 
+   * if we get error here we have trouble,
+   * silence unnecessary warnings
+   */
+  if(write(FD_ERR, err_msg, strlen(err_msg)));
+  if(write(FD_ERR, "\n", 1));
   exit(-1);
 }