file-reading-issue.js

var text = '';

// Fill the first chunk, except for the last byte
for (var i = 0; i < 256 * 1024 - 1; i++) {
    text += '.';
}

// In this example, the reading will split the character into '...\x01' and '\x53',
// which fails to decode in UTF-8
text += '\u0153';
text += '....'; // More padding, not required

function createFile(dirEntry, fileName) {
    dirEntry.getFile(fileName, {create: true, exclusive: false}, function(fileEntry) {
        writeFile(fileEntry, text);
    }, console.error);
}

function writeFile(fileEntry, text) {
    // Create a FileWriter object for our FileEntry (log.txt).
    fileEntry.createWriter(function(fileWriter) {

        fileWriter.onwriteend = function() {
            console.log("Successful file write...");
            readFile(fileEntry);
        };

        fileWriter.onerror = function(e) {
            console.log("Failed file write: " + e.toString());
        };

        fileWriter.write(text);
    });
}

function readFile(fileEntry) {
    fileEntry.file(function(file) {
        var reader = new FileReader();

        reader.onloadend = function() {
            var data = this.result;
            if (data) {
                console.log("Successful file read: " + data.length + " " + data.substring(data.length - 10));
            }
        };

        reader.onerror = function() {
            console.log('failed to read', this.error);
        };

        // If this is uncommented, reading works fine:
        // file.start = 1;

        reader.readAsText(file);

    }, console.error);
}

window.requestFileSystem(window.TEMPORARY, 5 * 1024 * 1024, function(fs) {
    createFile(fs.root, "newTempFile.txt", false);
}, console.error);