fork(1) download 
  1. -module(dinphil).
  2. -compile([export_all]).
  3.  
  4. college() ->
  5. 		%%Spawns all the Report, forks and philosophers
  6. 	Report = spawn(?MODULE, report, []),
  7.  
  8. 	F1 = spawn(?MODULE, initFork, ["Fork1", on_table, Report]),
  9. 	F2 = spawn(?MODULE, initFork, ["Fork2", on_table, Report]),
  10. 	F3 = spawn(?MODULE, initFork, ["Fork3", on_table, Report]),
  11. 	F4 = spawn(?MODULE, initFork, ["Fork4", on_table, Report]),
  12. 	F5 = spawn(?MODULE, initFork, ["Fork5", on_table, Report]),
  13.  
  14. 	Philo1 = spawn(?MODULE, initPhil, ["Bob", F1, F2, Report]),
  15. 	Philo2 = spawn(?MODULE, initPhil, ["Jim", F2, F3, Report]),
  16. 	Philo3 = spawn(?MODULE, initPhil, ["Tim", F3, F4, Report]),
  17. 	Philo4 = spawn(?MODULE, initPhil, ["Olly", F4, F5, Report]),
  18. 	Philo5 = spawn(?MODULE, initPhil, ["Ted", F5, F1, Report]),
  19. 	waitdone(5).
  20.  
  21. report() ->
  22. 	receive
  23. 		{fork, X} ->
  24. 			io:format ("~s~n", [X]);
  25. 		{taken_fork, X} ->
  26. 			io:format ("~s~n", [X]);
  27. 		{thinking, X} ->
  28. 			io:format ("~s~n", [X]);
  29. 		{hungry, X} ->
  30. 			io:format ("~s~n", [X]);
  31. 		{msg, X} ->
  32. 			io:format ("~s~n", [X]);
  33. 		Any ->
  34. 			io:format ("XX~s~n", [Any])
  35. 	end,
  36. 		report().
  37.  
  38. initFork(Name, Isavail, Report) ->
  39. 	Report ! {fork, string:concat(Name, ": has been spawned")},
  40. 	fork(Name, on_table, Report).
  41.  
  42. fork(Name, on_table, Report) ->
  43. 	receive
  44. 		{take_left, {Pidphil, Philname}} ->
  45. 			Pidphil ! {l_fork, self()},
  46. 			Report ! {taken_fork, string:concat(Philname, ": picked up a fork")},
  47. 			Report ! {fork, string:concat(Name, ": Is picked up")},
  48. 			fork(Name, in_hand, Report);
  49.  
  50. 		{take_right, {Pidphil, Philname}} -> 
  51. 			Pidphil ! {r_fork, self()},	
  52. 			Report ! {taken_fork, string:concat(Philname, ": picked up a fork")},
  53. 			Report ! {fork, string:concat(Name, ": Is picked up")},
  54. 			fork(Name, in_hand, Report)
  55. 	end;
  56.  
  57. fork(Name, in_hand, Report) ->
  58. 	receive
  59. 		{put_left, {Pidphil, Philname}} ->
  60. 			Pidphil ! {l_fork, self()},
  61. 			Report ! {taken_fork, string:concat(Philname, ": put down a fork")},
  62. 			Report ! {fork, string:concat(Name, ": Is put down")},
  63. 			fork(Name, on_table, Report);
  64.  
  65. 		{put_right, {Pidphil, Philname}} ->
  66. 			Pidphil ! {r_fork, self()},
  67. 			Report ! {taken_fork, string:concat(Philname, ": put down a fork")},
  68. 			Report ! {fork, string:concat(Name, ": Is put down")},
  69. 			fork(Name, on_table, Report)
  70. 		end.
  71.  
  72. initPhil(Name, LeftFork, RightFork, Report) ->
  73. 		Seed = random:seed(now()),
  74. 		philosopher(thinking, Name, LeftFork, RightFork, Report).
  75.  
  76. philosopher(thinking, Name, LFork, RFork, Report) ->
  77. 	Report ! {thinking, string:concat(Name, ": thinking")},
  78. 	timer:sleep(random:uniform(901)+99),
  79. 	philosopher(hungry, Name, LFork, RFork, Report);
  80.  
  81. philosopher(hungry, Name, LFork, RFork, Report) ->
  82. 	Report ! {hungry, string:concat(Name, ": is hungry")},
  83. 	LFork ! {take_left, {self(), Name}},
  84. 	RFork ! {take_right, {self(), Name}},
  85. 	receive 
  86. 	{l_fork, LFork} -> philosopher(has_left, Name, LFork, RFork, Report);
  87. 	{r_fork, RFork} -> philosopher(has_right, Name, LFork, RFork, Report)
  88. 	end;
  89.  
  90. philosopher(has_left, Name, LFork, RFork, Report) ->
  91. 	RFork ! {take_right, {self(), Name}},
  92. 	receive
  93. 		{r_fork, _ForkPID} -> philosopher(eating, Name, LFork, RFork, Report)
  94. 	end;
  95.  
  96. philosopher(has_right, Name, LFork, RFork, Report) ->
  97. 	LFork ! {take_left, {self(), Name}},
  98.  
  99. 	receive
  100. 		{l_fork, _ForkPID} -> philosopher(eating, Name, LFork, RFork, Report)
  101. 	end;
  102.  
  103. philosopher(eating, Name, LFork, RFork, Report) ->
  104. 	Report ! {hungry, string:concat(Name, ": is eating")},
  105. 	timer:sleep(random:uniform(901)+99),
  106. 	LFork ! {put_left, {self(), Name}},
  107. 	RFork ! {put_right, {self(), Name}},
  108. 	philosopher(thinking, Name, LFork, RFork, Report).
  109.  
  110. waitdone (0) -> finished ;
  111. waitdone (N) -> receive finished -> waitdone (N -1) end.
  112.  
  113.  
  114.  
  115.  
  116.  
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
dinphil:college().
compilation info 
/home/wV1pPi/prog.beam: Module name 'dinphil' does not match file name 'prog'
./prog.erl:14: Warning: variable 'Philo1' is unused
./prog.erl:15: Warning: variable 'Philo2' is unused
./prog.erl:16: Warning: variable 'Philo3' is unused
./prog.erl:17: Warning: variable 'Philo4' is unused
./prog.erl:18: Warning: variable 'Philo5' is unused
./prog.erl:38: Warning: variable 'Isavail' is unused
./prog.erl:73: Warning: variable 'Seed' is unused
stdout 
Standard output is empty
https://ideone.com/pk40bR
language:
Erlang (erl 21.3.8)
created:
10 years ago
visibility:
public

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