How to start a Linux server in the background ?

Thomas-Acia · 2015-09-17 11:51:12

Hi ab,

I would like to start my http server in the background on Linux. I tested ./SERVERNAME with '&' but it doesn't work. Do you have some ideas ?

Thank you

ab · 2015-09-17 14:18:15

Run the executable as a Linux daemon.

There are plenty of scripts around, allowing to do so.

Just ensure that your server won't use the console as interaction.
You would have to run it in a given blocking mode.

AOG · 2015-09-17 15:25:12

I just post the complete FPC mORMot daemon code, in case anybody else has also some use for it !

program RestServerLinuxARMDaemon;

{$mode objfpc}{$H+}
{$define UseCThreads}

uses
  {$IFDEF UNIX}{$IFDEF UseCThreads}
  cthreads,
  {$ENDIF}{$ENDIF}
  sysutils,
  Classes,
  mORMotHttpServer,
  RESTData,
  RESTServerClass,
  daemonapp;

Type

  { TTestDaemon }

  TTestDaemon = Class(TCustomDaemon)
  Private
    fORMServer: TSOHITServer;
    fHTTPServer: TSQLHttpServer;
  public
    Function Start : Boolean; override;
    Function Stop : Boolean; override;
    Function Pause : Boolean; override;
    Function Continue : Boolean; override;
    Function Execute : Boolean; override;
    Function ShutDown : Boolean; override;
    Function Install : Boolean; override;
    Function UnInstall: boolean; override;
  end;

{ TTestThread }

Procedure AWriteln(MSg : String; B : Boolean);
begin
  Application.Log(etcustom,Msg+BoolToStr(B));
end;

{ TTestDaemon }

function TTestDaemon.Start: Boolean;
begin
  Result:=inherited Start;
  AWriteln('Daemon Start',Result);
  AWriteln('Dir: '+GetAppConfigDir(False)+'data',True);
  if not DirectoryExists(GetAppConfigDir(False))
     then CreateDir(GetAppConfigDir(False));
  fORMServer := TSOHITServer.Create(GetAppConfigDir(False)+'data','root');
  fHTTPServer := TSQLHttpServer.Create(HTTP_PORT,[fORMServer]);
end;

function TTestDaemon.Stop: Boolean;
begin
  Result:=inherited Stop;
  AWriteln('Daemon Stop: ',Result);
  FreeAndNil(fHTTPServer);
  FreeAndNil(fORMServer);
end;

function TTestDaemon.Pause: Boolean;
begin
  Result:=inherited Pause;
  AWriteln('Daemon pause: ',Result);
end;

function TTestDaemon.Continue: Boolean;
begin
  Result:=inherited Continue;
  AWriteln('Daemon continue: ',Result);
end;

function TTestDaemon.Execute: Boolean;
begin
  Result:=inherited Execute;
  AWriteln('Daemon execute: ',Result);
end;

function TTestDaemon.ShutDown: Boolean;
begin
  Result:=inherited ShutDown;
  AWriteln('Daemon Shutdown: ',Result);
  Try
    Try
      FreeAndNil(fHTTPServer);
    Except
    End;
  Finally
    FreeAndNil(fORMServer);
  End;
end;

function TTestDaemon.Install: Boolean;
begin
  Result:=inherited Install;
  AWriteln('Daemon Install: ',Result);
end;

function TTestDaemon.UnInstall: boolean;
begin
  Result:=inherited UnInstall;
  AWriteln('Daemon UnInstall: ',Result);
end;

Type

  { TTestDaemonMapper }

  TTestDaemonMapper = Class(TCustomDaemonMapper)
    Constructor Create(AOwner : TComponent); override;
  end;

{ TTestDaemonMapper }

constructor TTestDaemonMapper.Create(AOwner: TComponent);

Var
  D : TDaemonDef;

begin
  inherited Create(AOwner);
  D:=DaemonDefs.Add as TDaemonDef;
  D.DisplayName:='Test daemon';
  D.Name:='TestDaemon';
  D.DaemonClassName:='TTestDaemon';
  D.WinBindings.ServiceType:=stWin32;
end;

begin
  RegisterDaemonClass(TTestDaemon);
  RegisterDaemonMapper(TTestDaemonMapper);
  Application.Title:='Daemon test application';
  Application.Run;
end.

And the systemd script:

[Unit]
Description=mORMot server
After=network.target

[Service]
User=superdad
Type=simple
ExecStart=/home/superdad/tmp/daemon -r
RemainAfterExit=yes
TimeoutSec=25

[Install]
WantedBy=multi-user.target

Last edited by AOG (2015-09-17 15:27:57)

Thomas-Acia · 2015-09-18 06:59:32

Thank you for your help AOG. It will be very usefull

oerjann · 2016-02-03 15:22:23

It looks like the daemon code posted by AOG need to be updated in order to compile. I can not find a class called TSOHITServer in the mORMot source code.

edwinsn · 2016-05-15 10:13:37

oerjann wrote:

It looks like the daemon code posted by AOG need to be updated in order to compile. I can not find a class called TSOHITServer in the mORMot source code.

TSOHITServer should be AOG's derived class, but not a class included by the mORMot framework...

alex4z · 2016-06-02 02:21:41

Here is a simple implementation of a FPC/Lazarus/Codetyphon daemon

program eventserv;

//{$define Debug}

uses
  {$ifdef linux}
    cthreads,
    cmem, // the c memory manager is on some systems much faster for multi-threading
  {$endif}

sysutils,classes,unix, baseunix,lnet;

type
{ TLTCPTest }

  TLTCPServer = class
   private
    FCon: TLTCP; // THE server connection
    procedure OnEr(const msg: string; aSocket: TLSocket);
    procedure OnAc(aSocket: TLSocket);
    procedure OnRe(aSocket: TLSocket);
    procedure OnDs(aSocket: TLSocket);
   public
    constructor Create;
    destructor Destroy; override;
    procedure Run; // main loop with CallAction
  end;
//===========================
Var
{ vars for daemonizing }
aOld,aTerm: pSigActionRec;
ps1  : psigset;
sSet : cardinal;
pid  : pid_t;
zerosigs : sigset_t;
//err: LongInt;
//mypid:integer;
TCP: TLTCPServer;
//==================================================================================
procedure TLTCPServer.OnEr(const msg: string; aSocket: TLSocket);
begin
//aSocket.Disconnect(true);
{$ifdef DEBUG}
Writeln(logfile, datetimetostr(now)+' TCPServer ERROR: '+msg+' '+aSocket.PeerAddress+CR+LF);
{$endif}
end;
//==================================================================================
procedure TLTCPServer.OnAc(aSocket: TLSocket); 
begin
//if BLACKLIST.Find(aSocket.PeerAddress,ind) then aSocket.Disconnect(True);
{$ifdef DEBUG}
//Writeln(logfile, datetimetostr(now)+' Accepted connection from: '+aSocket.PeerAddress+CR+LF);
{$endif}
end;
//==================================================================================
procedure TLTCPServer.OnDs(aSocket: TLSocket); 
begin
 // Writeln('Lost connection'); // write info if connection was lost
end;
//==================================================================================
procedure TLTCPServer.OnRe(aSocket: TLSocket);  // on recieve message

begin
///////////////////////////////////////// your functionality
end;
//==================================================================================
constructor TLTCPServer.Create;
begin
  FCon := TLTCP.Create(nil); // create new TCP connection
  FCon.OnError := @OnEr;     // assign all callbacks
  FCon.OnReceive := @OnRe;
  FCon.OnDisconnect := @OnDs;
  FCon.OnAccept := @OnAc;
  FCon.Timeout := 150; // responsive enough, but won't hog cpu
  FCon.ReuseAddress := True;
end;
//==================================================================================
destructor TLTCPServer.Destroy;
begin
  FCon.Free; // free the TCP connection
  inherited Destroy;
end;
//=================================== MAIN PROC ============================
procedure TLTCPServer.Run;
var counter,i:integer;
 myport:word;

begin
   ///..............
    if FCon.Listen(myPort) then
      begin // if listen went ok
        repeat
        inc(counter);
        FCon.Callaction; // eventize the lNet
        // some to do
        until Quit; // until user quit
      end;// else // listen
    {$ifdef DEBUG}
   // Writelog(datetimetostr(now)+' Listener not start!!! Port may be busy!!!');
    {$endif} ;
  
end;
{ handle SIGTERM }
//==================================================================================================
procedure DoSig(sig : longint);cdecl;
begin
     case sig of
     SIGTERM : Quit := true;
     end;
//---
{$ifdef DEBUG}
Writeln(logfile, datetimetostr(now)+' Closed by SIGTERM');
CloseFile(logfile);
{$endif}
end;

//==================================================================================================
procedure RunDaemon();

begin
//writeln('Connecting...');
{$hints off}
FpsigEmptySet(zerosigs);
{$hints on}
{ set global daemon booleans }
//bTerm := false;
{ block all signals except -TERM }
sSet := $ffffbffe;
ps1 := @sSet;
fpsigprocmask(sig_block,ps1,nil);
{ setup the signal handlers }
new(aOld);
new(aTerm);
aTerm^.sa_handler{.sh} := SigactionHandler(@DoSig);
aTerm^.sa_mask := zerosigs;
aTerm^.sa_flags := 0;
fpSigAction(SIGTERM,aTerm,aOld);
{ daemonize }
deletefile(iam);
pid := fpFork;
case pid of
0 : begin { we are in the child }
Close(input); { close standard in }
Assign(input,'/dev/null');
ReWrite(input);
Close(output); { close standard out }
Assign(output,'/dev/null');
ReWrite(output);
Close(stderr); { close standard error }
pid:=fpGetPid;
//createpidfile(pid);
end;
-1 :begin
//WriteLn('forking error, process not demonized!');
halt(1);
    end;
else begin
//Halt;
FpExit(0);{ successful fork, so parent dies }
end;
end;
//------------------------------------
if isroot then
begin
TCP := TLTCPServer.Create;
TCP.Run;
TCP.Free;
end;
//------------------------------------
//deletefile(mypath+'d.pid');
end;
//==================================================================================================


Begin

//remotekilled:=false;
mypath:=extractfilepath(paramstr(0));
iam:=paramstr(0);
isroot:=true;
//**Check for superuser rights**
 if fpGetUID <> 0 then
begin
//Writeln('Error: Need superuser rights');
isroot:=false;
//halt;
end;

RunDaemon;

End.

moctes · 2017-08-03 01:16:47

Hello everyone,

I finally found sometime to setup a linux VM and until now everything has been smooth ( fpcupdeluxe gave me big push here), now I want to make a simple daemon for querying static data I already have on a SQLite .db file, I post on this thread because it is sticked out here and I have one simple question related to linux servers.

Seems like I have to put these compiler directives on my lpr :

{$I Synopse.inc}

uses
   ...
   {$I SynDprUses.inc}
   ...

Will that be enough ? Or there is any other directive I have to add

I'm working with current trunk ( Lazarus & FPC ) and the version mORMot which TestSQL3 reports is:

Using mORMot 1.18.3765 FTS3
Running on Linux-4.4.0-88-generic #111-Ubuntu SMP Thu Jul 20 09:32:39 UTC 2017
TSQLite3LibraryStatic 3.19.2 with internal MM
Generated with: Free Pascal 3.1.1 MOP 64 bit compiler

Thank you

ab · 2017-08-03 07:51:44

Check https://synopse.info/files/html/Synopse … l#TITL_143
Information here is not fully applying to FpcUpDeluxe, but you got the information about .inc files.

macfly · 2019-06-12 17:29:09

I'll share this tip, which I found when searching for a simpler solution.

$ (./my_app &) &

Obviously is not a complete Daemon, but It Works!
And you do not need to modify the application.

https://stackoverflow.com/questions/343 … ipt-daemon

ab · 2019-06-13 08:32:20

Note: the TSynDaemon class as implemented in mORMotService.pas works fine on production since months.

dcoun · 2022-05-29 13:05:19

Check this thread too
https://synopse.info/forum/viewtopic.php?id=6395

Last edited by dcoun (2022-10-28 14:50:45)

mORMot Open Source

#1 2015-09-17 11:51:12

How to start a Linux server in the background ?

#2 2015-09-17 14:18:15

Re: How to start a Linux server in the background ?

#3 2015-09-17 15:25:12

Re: How to start a Linux server in the background ?

#4 2015-09-18 06:59:32

Re: How to start a Linux server in the background ?

#5 2016-02-03 15:22:23

Re: How to start a Linux server in the background ?

#6 2016-05-15 10:13:37

Re: How to start a Linux server in the background ?

#7 2016-06-02 02:21:41

Re: How to start a Linux server in the background ?

#8 2017-08-03 01:16:47

Re: How to start a Linux server in the background ?

#9 2017-08-03 07:51:44

Re: How to start a Linux server in the background ?

#10 2019-06-12 17:29:09

Re: How to start a Linux server in the background ?

#11 2019-06-13 08:32:20

Re: How to start a Linux server in the background ?

#12 2022-05-29 13:05:19

Re: How to start a Linux server in the background ?

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