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var is_windows = process.platform === 'win32';
var common = require('../common');
var assert = require('assert'),
os = require('os'),
util = require('util'),
spawn = require('child_process').spawn;
// We're trying to reproduce:
// $ echo "hello\nnode\nand\nworld" | grep o | sed s/o/a/
var grep, sed, echo;
if (is_windows) {
grep = spawn('grep', ['--binary', 'o']),
sed = spawn('sed', ['--binary', 's/o/O/']),
echo = spawn('cmd.exe',
['/c', 'echo', 'hello&&', 'echo',
'node&&', 'echo', 'and&&', 'echo', 'world']);
} else {
grep = spawn('grep', ['o']),
sed = spawn('sed', ['s/o/O/']),
echo = spawn('echo', ['hello\nnode\nand\nworld\n']);
}
/*
* grep and sed hang if the spawn function leaks file descriptors to child
* processes.
* This happens when calling pipe(2) and then forgetting to set the
* FD_CLOEXEC flag on the resulting file descriptors.
*
* This test checks child processes exit, meaning they don't hang like
* explained above.
*/
// pipe echo | grep
echo.stdout.on('data', function(data) {
console.error('grep stdin write ' + data.length);
if (!grep.stdin.write(data)) {
echo.stdout.pause();
}
});
grep.stdin.on('drain', function(data) {
echo.stdout.resume();
});
// propagate end from echo to grep
echo.stdout.on('end', function(code) {
grep.stdin.end();
});
echo.on('exit', function() {
console.error('echo exit');
});
grep.on('exit', function() {
console.error('grep exit');
});
sed.on('exit', function() {
console.error('sed exit');
});
// pipe grep | sed
grep.stdout.on('data', function(data) {
console.error('grep stdout ' + data.length);
if (!sed.stdin.write(data)) {
grep.stdout.pause();
}
});
sed.stdin.on('drain', function(data) {
grep.stdout.resume();
});
// propagate end from grep to sed
grep.stdout.on('end', function(code) {
console.error('grep stdout end');
sed.stdin.end();
});
var result = '';
// print sed's output
sed.stdout.on('data', function(data) {
result += data.toString('utf8', 0, data.length);
util.print(data);
});
sed.stdout.on('end', function(code) {
assert.equal(result, 'hellO' + os.EOL + 'nOde' + os.EOL +'wOrld' + os.EOL);
});
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