Test JS script file

Selected file: fs-sync2.js
Compare console.log() outputs in browser and NodeJS.
Notice: Open browser's console in FireBUG!

  1. 05define_functions.js
  2. 10module_basic1.js
  3. 10module_basic2.js
  4. 10module_basic3.js
  5. 11module_nesting.js
  6. file.js
  7. fs-async.js
  8. fs-async2.js
  9. fs-async3.js
  10. fs-sync.js
  11. fs-sync2.js
  12. http.js
  13. index.html
  14. index.js
  15. my_modules
  16. net.js
  17. npm-debug.log
  18. package.json
  19. promises
  20. socket.js
  21. sys.js
  22. testfiles

..:: Source code - fs-sync2.js ::..

/*
This example shows synchronous execution, blocking code.
console.log(contents); blocks process and that's why
console.log('Do something else!'); must wait

Max file that didn't crash nodeJS had 350MB
 */

//load modules
var fs = require('fs');

//synchronous file reading
var content = fs.readFile('./testfiles/largefile350mb.txt', 'utf8');
console.log(content);  //returns 'undefined' because readFile requires callback and dont return any value

//here process is blocked while file is not read completely. After that next console.log(); continue

console.log('Do something else!');

/*
Conclusion: Due to asynchronous execution, first is file dumped then appear 'Do something else'.
That's because console.log('Do something else!'); waits fs.readFileSync('largefile350mb.txt', 'utf8'); to be finished.
 */
 

..:: NodeJS Console - fs-sync2.js ::..

$ node fs-sync2.js 

		
		


		
		
$ps -aux | grep node (list all node processes)
sasa        1273  0.6  0.4 1303816 80552 ?       Ssl  Sep21 232:44 node /home/sasa/.pm2/modules/pm2-logrotate/node_modules/pm2-logr
sasa        1293  1.2  0.8 11722984 135116 ?     Ssl  Sep21 463:19 node /home/sasa/dex8/dex8-api/starter.js
sasa        1298  0.4  0.4 1305152 72500 ?       Ssl  Sep21 178:49 node /home/sasa/regoch/regoch-www/server
sasa        1309  0.4  0.4 1299340 66604 ?       Ssl  Sep21 161:59 node /home/sasa/dex8/dex8-panel/server/index.js
sasa        1320  0.9  0.6 11811008 103620 ?     Ssl  Sep21 339:55 node /home/sasa/dex8/dex8-www/server/index.js
sasa        1329  0.6  0.5 11806180 94696 ?      Ssl  Sep21 238:41 node /home/sasa/mikosoft_hr/www-mikosoft-hr/server/index.js
sasa        1340  0.8  0.5 1198908 82132 ?       Ssl  Sep21 313:43 node /home/sasa/mikosoft-info/api-mikosoft-info/starter.js
sasa        1357  0.4  0.4 1303220 73124 ?       Ssl  Sep21 163:25 node /home/sasa/mikosoft-info/www-mikosoft-info/server/index.js
sasa        1381  0.4  0.3 1297080 65288 ?       Ssl  Sep21 160:57 node /home/sasa/dex8/dex8-kiosk/server/index.js
sasa        1417  0.7  0.5 11823280 98000 ?      Ssl  Sep21 260:09 node /home/sasa/mikosoft-info/dodo-mikosoft-info/server/index.js
sasa        1477  0.4  0.4 11794680 77472 ?      Ssl  Sep21 176:19 node /home/sasa/@mikosoft/dodo-examples/server/index.js
sasa        1966  1.0  0.8 11833412 131928 ?     Ssl  Sep21 387:11 node /home/sasa/mikosoft-info/crypto-mikosoft-info/server/index.
sasa      811323  0.0  0.1 163020 18992 ?        Ssl  23:37   0:00 node /usr/local/lib/node_modules/pm2/lib/ProcessContainerFork.js
www-data  811324  0.0  0.0   2608   592 ?        S    23:37   0:00 sh -c ps -aux | grep node
www-data  811326  0.0  0.0   3304   656 ?        S    23:37   0:00 grep node
sasa     1026987  0.8  0.6 1148924 104464 ?      Ssl  Oct15  18:27 node /home/sasa/voovuu/voovuu-api/starter.js
sasa     1041499  0.8  0.8 22320204 138848 ?     Ssl  Sep27 244:59 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041553  2.2  0.9 22331300 151892 ?     Ssl  Sep27 634:30 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041586  0.4  0.4 1167720 67288 ?       Ssl  Sep27 121:51 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041612  0.4  0.4 1166688 65972 ?       Ssl  Sep27 121:42 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041650  0.4  0.4 1168224 68420 ?       Ssl  Sep27 122:15 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041678  0.4  0.4 1167204 66704 ?       Ssl  Sep27 121:53 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041713  0.4  0.3 1166180 64596 ?       Ssl  Sep27 121:36 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041745  0.4  0.4 1166948 65984 ?       Ssl  Sep27 121:49 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041773  0.4  0.3 1099364 64572 ?       Ssl  Sep27 118:10 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1041811  0.4  0.3 1099104 64444 ?       Ssl  Sep27 119:01 node /home/sasa/dex8/dex8-worker/starter.js
sasa     1617980  4.9  1.0 11877776 167396 ?     Ssl  Oct15  90:54 node /home/sasa/voovuu/voovuu-pub/server/index.js