QT Process Basics (i) how QT determines that another process is running

The QT library does not seem to have a complete cross-platform solution, and you may need to judge by your own platform.

Windows can use OpenProcess to obtain relevant information using the methods mentioned above. Termination is simple:

ShellExecute (0, "open", "TASKKILL", (Processname,null, sw_hide);

Other platforms need to find a way to locate the PID of the process (such as invoking the system's PS command for filtering lookups),

Linux opens/proc/pid/cmdline view process status.

Sun System opens/proc/pid/psinfo view process status.

---------------------------Win Platform------------------------------------------------

Attached code:

const char DESTPROC[19] = "cmd.exe";
DWORD pid = processtopid (Destproc);
return to 0 is no

2. DWORD processtopid(const char *inputprocessname)
   

4. {
   

6. DWORD aprocesses[1024x768], cbneeded, cprocesses;
   

8. unsigned int i;
   

10. HANDLE hprocess = NULL;
    

12. hmodule hmod = NULL;
    

14. Char szprocessname[max_path] = "unknownprocess";
    

16. 
    

18. Addprivilege(se_debug_name);
    

20. 
    

22. //Calculate how many processes are currently in place, aprocesses[] is used to store valid processes PIDs
    

24. if ( ! EnumProcesses( aprocesses, sizeof(aprocesses), & cbneeded ) )
    

26. {
    

28. return 0;
    

30. }
    

32. 
    

34. Cprocesses = cbneeded / sizeof(DWORD);
    

36. //To traverse all processes by a valid PID
    

38. for ( i = 0; i < cprocesses; i++ )
    

40. {
    

42. //Open a specific PID process
    

44. hprocess = openprocess( process_query_information |
    

46. Process_vm_read,
    

48. FALSE , aprocesses[i]);
    

50. //Get the process name of the specific PID
    

52. if ( hprocess )
    

54. {
    

56. if ( enumprocessmodules( hprocess, &hmod, sizeof( Hmod), &cbneeded ) )
    

58. {
    

60. GetModuleBaseName( hprocess, hmod,
    

62. szProcessName, sizeof(szprocessname) );
    

64. //The process name to be obtained is compared with the input process name, as the same will return the process PID
    

66. if (! stricmp(szprocessname, inputprocessname))
    

68. {
    

70. CloseHandle( hprocess );
    

72. return aprocesses[i];
    

74. }
    

76. }
    

78. }//end of If (hprocess)
    

80. }//end of For
    

82. //did not find the corresponding process name, returned 0
    

84. CloseHandle( hprocess );
    

86. return 0;
    

88. }

You can also enumerate the application names of all the processes and then judge the name of the application.

2. DWORD getprocessidfromname(lpctstr name)
   

4. {
   

6. PROCESSENTRY32 PE;
   

8. DWORD id=0;
   

10. HANDLE hsnapshot=createtoolhelp32snapshot(th32cs_snapprocess,0);
    

12. PE. dwsize=sizeof(PROCESSENTRY32);
    

14. if (! Process32First(hsnapshot,&pe))
    

16. return 0;
    

18. while (1)
    

20. {
    

22. PE. dwsize=sizeof(PROCESSENTRY32);
    

24. if (process32next(hsnapshot,&pe)==FALSE )
    

26. Break ;
    

28. if (strcmp(pe. Szexefile,name)==0)
    

30. {
    

32. ID=pe. Th32processid;
    

34. 
    

36. Break ;
    

38. }
    

40. 
    

42. 
    

44. }
    

46. CloseHandle(hsnapshot);
    

48. return ID;
    

50. }

QT Process Basics (i) how QT determines that another process is running