Uncompleted home task for 28.10

[kostyamikhaylov]

Реализовал read/write без обработки множественного доступа к очереди

cat /dev/dummy

[ 70.024624] dummy: opened.
[ 70.025521] dummy: closed.

echo "msg" > /dev/dummy

[ 83.638764] dummy: opened.
[ 83.640483] dummy: closed.

echo "msg2" > /dev/dummy

[ 87.277430] dummy: opened.
[ 87.278202] dummy: closed.

cat /dev/dummy

[ 89.583134] dummy: opened.
msg
[ 89.584001] dummy: closed.

cat /dev/dummy

[ 90.523417] dummy: opened.
msg2
[ 90.524281] dummy: closed.

cat /dev/dummy

[ 91.416847] dummy: opened.
[ 91.417282] dummy: closed.

[AblakatovMikhail]

Драйвер вмещает слишком мало сообщений. Возможно, это связано с размером буфера? Можно ли сделать его динамическим?

Запись:

# for i in  $(seq 1 1024) ; do echo "Message $i with some additional text to inc
rease its size" > /dev/dummy ; done
[  164.937616] dummy: opened.
[  164.937983] dummy: closed.
[  164.938303] dummy: opened.
[  164.938590] dummy: closed.
[  164.940991] dummy: opened.
[  164.941288] dummy: closed.
[  164.941601] dummy: opened.
[  164.941881] dummy: closed.
[  164.942177] dummy: opened.
[  164.942451] dummy: closed.
[  164.942882] dummy: opened.
[  164.945957] dummy: closed.
[  164.946284] dummy: opened.
[  164.946573] dummy: closed.
[  164.948833] dummy: opened.
[  164.949141] dummy: closed.
[  164.949438] dummy: opened.
[  164.949721] dummy: closed.
[  164.950027] dummy: opened.
[  164.950319] dummy: closed.
[  164.950626] dummy: opened.
[  164.953858] dummy: closed.
[  164.954188] dummy: opened.
[  164.954484] dummy: closed.
[  164.954946] dummy: opened.
[  164.957386] dummy: closed.
[  164.957709] dummy: opened.
[  164.957996] dummy: closed.
[  164.958313] dummy: opened.
[  164.958606] dummy: closed.
[  164.961244] dummy: opened.
[  164.961568] dummy: closed.
[  164.961879] dummy: opened.
[  164.962173] dummy: closed.
[  164.962479] dummy: opened.
[  164.965050] dummy: closed.
[  164.965385] dummy: opened.
[  164.965687] dummy: closed.
[  164.965990] dummy: opened.
[  164.966275] dummy: closed.
[  164.966575] dummy: opened.
[  164.969509] dummy: closed.
[  164.969839] dummy: opened.
[  164.970134] dummy: closed.
[  164.970441] dummy: opened.
[  164.970751] dummy: closed.
[  164.973220] dummy: opened.
[  164.973499] dummy: closed.
[  164.973749] dummy: opened.
[  164.973985] dummy: closed.
[  164.974225] dummy: opened.
[  164.974456] dummy: closed.
[  164.974696] dummy: opened.
[  164.976687] dummy: closed.
[  164.976872] dummy: opened.
[  164.977031] dummy: closed.
[  164.977193] dummy: opened.
[  164.977349] dummy: closed.
[  164.977512] dummy: opened.
[  164.977669] dummy: closed.
[  164.977833] dummy: opened.
[  164.977989] dummy: closed.
[  164.978162] dummy: opened.
[  164.978299] dummy: closed.
[  164.978441] dummy: opened.
[  164.978577] dummy: closed.
[  164.978807] dummy: opened.
[  164.981770] dummy: closed.
[  164.981931] dummy: opened.
[  164.982069] dummy: closed.
[  164.982218] dummy: opened.
[  164.982352] dummy: closed.
[  164.982495] dummy: opened.
[  164.982633] dummy: closed.
[  164.984294] dummy: opened.
[  164.984442] dummy: closed.
[  164.984600] dummy: opened.
[  164.984754] dummy: closed.
[  164.984909] dummy: opened.
[  164.985051] dummy: closed.
[  164.985200] dummy: opened.
[  164.985339] dummy: closed.
[  164.985483] dummy: opened.
[  164.985622] dummy: closed.
[  164.985759] dummy: opened.
[  164.985894] dummy: closed.
[  164.986035] dummy: opened.
[  164.986187] dummy: closed.
[  164.986332] dummy: opened.
[  164.986466] dummy: closed.
[  164.986606] dummy: opened.
[  164.990108] dummy: closed.
[  164.990264] dummy: opened.
[  164.990402] dummy: closed.
[  164.990546] dummy: opened.
[  164.990681] dummy: closed.
[  164.990836] dummy: opened.
[  164.990992] dummy: closed.
[  164.992755] dummy: opened.
[  164.992907] dummy: closed.
[  164.993051] dummy: opened.
^C[  167.135030] dummy: closed.

Чтение

# while (true) ; do read_msg=$(cat /dev/dummy) ; if [ -z $read_msg ] ; then brea
k ; fi ; echo $read_msg ; done
[  169.850338] dummy: opened.
[  169.852571] dummy: closed.
sh: 1: unknown operand
Message 1 with some additional text to increase its size
[  169.876611] dummy: opened.
[  169.877767] dummy: closed.
sh: 2: unknown operand
Message 2 with some additional text to increase its size
[  169.902140] dummy: opened.
[  169.904123] dummy: closed.
sh: 3: unknown operand
Message 3 with some additional text to increase its size
[  169.918066] dummy: opened.
[  169.918685] dummy: closed.
sh: 4: unknown operand
Message 4 with some additional text to increase its size
[  169.930510] dummy: opened.
[  169.931578] dummy: closed.
sh: 5: unknown operand
Message 5 with some additional text to increase its size
[  169.943316] dummy: opened.
[  169.943870] dummy: closed.
sh: 6: unknown operand
Message 6 with some additional text to increase its size
[  169.955702] dummy: opened.
[  169.956249] dummy: closed.
sh: 7: unknown operand
Message 7 with some additional text to increase its size
[  169.968342] dummy: opened.
[  169.968891] dummy: closed.
sh: 8: unknown operand
Message 8 with some additional text to increase its size
[  169.980761] dummy: opened.
[  169.981298] dummy: closed.
sh: 9: unknown operand
Message 9 with some additional text to increase its size
[  169.993378] dummy: opened.
[  169.993914] dummy: closed.
sh: 10: unknown operand
Message 10 with some additional text to increase its size
[  170.005734] dummy: opened.
[  170.006256] dummy: closed.
sh: 11: unknown operand
Message 11 with some additional text to increase its size
[  170.018317] dummy: opened.
[  170.019366] dummy: closed.
sh: 12: unknown operand
Message 12 with some additional text to increase its size
[  170.031047] dummy: opened.
[  170.031596] dummy: closed.
sh: 13: unknown operand
Message 13 with some additional text to increase its size
[  170.043438] dummy: opened.
[  170.043945] dummy: closed.
sh: 14: unknown operand
Message 14 with some additional text to increase its size
[  170.055710] dummy: opened.
[  170.056232] dummy: closed.
sh: 15: unknown operand
Message 15 with some additional text to increase its size
[  170.068307] dummy: opened.
[  170.068807] dummy: closed.
sh: 16: unknown operand
Message 16 with some additional text to increase its size
[  170.080652] dummy: opened.
[  170.081156] dummy: closed.
sh: 17: unknown operand
Message 17 with some additional text to increase its size
[  170.093153] dummy: opened.
[  170.093640] dummy: closed.
sh: 18: unknown operand
Message 18 with some additional text to increase its size
[  170.105451] dummy: opened.
[  170.105939] dummy: closed.
sh: 19: unknown operand
Message 19 with some additional text to increase its size
[  170.118959] dummy: opened.
[  170.119622] dummy: closed.
sh: 20: unknown operand
Message 20 with some additional text to increase its size
[  170.132248] dummy: opened.
[  170.132885] dummy: closed.
sh: 21: unknown operand
Message 21 with some additional text to increase its size
[  170.144970] dummy: opened.
[  170.145461] dummy: closed.
sh: 22: unknown operand
Message 22 with some additional text to increase its size
[  170.157337] dummy: opened.
[  170.157802] dummy: closed.
sh: 23: unknown operand
Message 23 with some additional text to increase its size
[  170.169652] dummy: opened.
[  170.170118] dummy: closed.
sh: 24: unknown operand
Message 24 with some additional text to increase its size
[  170.181927] dummy: opened.
[  170.182378] dummy: closed.
sh: 25: unknown operand
Message 25 with some additional text to increase its size
[  170.194369] dummy: opened.
[  170.195314] dummy: closed.
sh: 26: unknown operand
Message 26 with some additional text to increase its size
[  170.207079] dummy: opened.
[  170.207523] dummy: closed.
sh: 27: unknown operand
Message 27 with some additional text to increase its size
[  170.219394] dummy: opened.
[  170.219829] dummy: closed.
sh: 28: unknown operand
Message 28 with some additional text to increase its size
[  170.231581] dummy: opened.
[  170.232028] dummy: closed.
sh: 29: unknown operand
Message 29 with some additional text to increase its size
[  170.243753] dummy: opened.
[  170.244165] dummy: closed.
sh: 30: unknown operand
Message 30 with some additional text to increase its size
[  170.256176] dummy: opened.
[  170.256580] dummy: closed.
sh: 31: unknown operand
Message 31 with some additional text to increase its size
[  170.268219] dummy: opened.
[  170.268626] dummy: closed.
sh: 32: unknown operand
Message 32 with some additional text to increase its size
[  170.280375] dummy: opened.
[  170.280780] dummy: closed.
sh: 33: unknown operand
Message 33 with some additional text to increase its size
[  170.292575] dummy: opened.
[  170.292970] dummy: closed.
sh: 34: unknown operand
Message 34 with some additional text to increase its size
[  170.304740] dummy: opened.
[  170.305152] dummy: closed.
sh: 35: unknown operand
Message 35 with some additional text to increase its size
[  170.316876] dummy: opened.
[  170.317265] dummy: closed.
sh: 36: unknown operand
Message 36 with some additional text to increase its size
[  170.328928] dummy: opened.
[  170.329297] dummy: closed.
sh: 37: unknown operand
Message 37 with some additional text to increase its size
[  170.340996] dummy: opened.
[  170.341367] dummy: closed.
sh: 38: unknown operand
Message 38 with some additional text to increase its size
[  170.353107] dummy: opened.
[  170.353469] dummy: closed.
sh: 39: unknown operand
Message 39 with some additional text to increase its size
[  170.365279] dummy: opened.
[  170.365645] dummy: closed.
sh: 40: unknown operand
Message 40 with some additional text to increase its size
[  170.377375] dummy: opened.
[  170.377720] dummy: closed.
sh: 41: unknown operand
Message 41 with some additional text to increase its size
[  170.389331] dummy: opened.
[  170.389687] dummy: closed.
sh: 42: unknown operand
Message 42 with some additional text to increase its size
[  170.401533] dummy: opened.
[  170.401877] dummy: closed.
sh: 43: unknown operand
Message 43 with some additional text to increase its size
[  170.413801] dummy: opened.
[  170.414157] dummy: closed.
sh: 44: unknown operand
Message 44 with some additional text to increase its size
[  170.425829] dummy: opened.
[  170.426169] dummy: closed.
sh: 45: unknown operand
Message 45 with some additional text to increase its size
[  170.437928] dummy: opened.
[  170.438259] dummy: closed.
sh: 46: unknown operand
Message 46 with some additional text to increase its size
[  170.449979] dummy: opened.
[  170.450290] dummy: closed.
sh: 47: unknown operand
Message 47 with some additional text to increase its size
[  170.462157] dummy: opened.
[  170.462474] dummy: closed.
sh: 48: unknown operand
Message 48 with some additional text to increase its size
[  170.474205] dummy: opened.
[  170.474509] dummy: closed.
sh: 49: unknown operand
Message 49 with some additional text to increase its size
[  170.486393] dummy: opened.
[  170.486695] dummy: closed.
sh: 50: unknown operand
Message 50 with some additional text to increase its size
[  170.498335] dummy: opened.
[  170.498495] dummy: closed.