Simple answer, I have no idea.
So as you mentioned the offset can not be > 4gb... So far I have not found anyone who calls GetPartialObject, so not sure.
I can confirm the timings!
>1 hour to copy over MSC to USB SSD drive. I have not waited that long yet...On the one sound file I tried on Windows, it downloaded the whole thing. However running it on RPI5 the VLC media player is doing partials.
void test_write_file(int ch) {
test_file_write_size = CommandLineReadNextNumber(ch, test_file_write_size);
test_file_size = CommandLineReadNextNumber(ch, test_file_size);
if (ch >= ' ') {
Serial.setTimeout(0);
int cb = Serial.readBytesUntil( '\n', test_file_name, sizeof(test_file_name));
}
File testFile; // Specifes that dataFile is of File type
myfs->remove(test_file_name); // try to remove files before as to force it to reallocate the file...
testFile = myfs->open(test_file_name, FILE_WRITE_BEGIN);
if (!testFile) {
Serial.printf("Failed to open %s\n", test_file_name);
return;
}
Serial.printf("Start write file: %s length:%llu Write Size:%u\n", test_file_name, test_file_size, test_file_write_size);
uint32_t cb_write = test_file_write_size;
uint64_t cb_left = test_file_size;
uint8_t fill_char = '0';
test_file_buffer[cb_write - 2] = '\n'; // make in to text...
uint32_t percent_left_prev = (cb_left * 100ul) / test_file_size;
elapsedMillis em;
while (cb_left) {
if (cb_left < cb_write) cb_write = cb_left;
memset(test_file_buffer, cb_write - 1, fill_char);
testFile.write(test_file_buffer, cb_write);
fill_char = (fill_char == '9')? '0' : fill_char + 1;
cb_left -= cb_write;
uint32_t percent_left = (cb_left * 100ul) / test_file_size;
while (percent_left < percent_left_prev) {
percent_left_prev--;
Serial.write('.');
}
}
testFile.close();
Serial.printf("\nTime to write: %u\n", (uint32_t)em);
}Start write file: large_test_file.txt length:5000000000 Write Size:512
Time to write: 3156663Start write file: large_test_file.txt length:5000000000 Write Size:512
....................................................................................................
Time to write: 223827 size_t cb_written = testFile.write(test_file_buffer, cb_write);
if (cb_written != cb_write) {
uint64_t cb_output = test_file_size - cb_left;
Serial.printf("\n\!Write failed cb left:%llu output:%llu(0x%llx)\n", cb_left, cb_output, cb_output);
break;
}Storage Index 3 Name: MSC0 Selected
Start write file: large_test_file.txt length:5000000000 Write Size:4096
......................................................................................
!Write failed cb left:705036800 output:4294963200(0xfffff000)
Time to write: 398205
Yep - My 128GB SDCards were exfat... So was able to upload, others failed and left the disk with size like 3.9GB... I just confirmed I could create a 5GB file on my other SSD that I reformatted to exFat... Now to try to download that file.
Yep noticed the same thing. Still trying to get everything synched on my win 10 machine
Yep the current upload/download tries to write out each packet as received (or sent) so either 500 (first) and 512 after that.
Retrieving/assigning the volume label, for one thing. Also retrieving the max supported filename length and checking if the FS is read-only without actually attempting to write something.
virtual int ioctl(uint32_t function_num, const void* in_buffer, size_t in_length, void* out_buffer, size_t out_length) { return -1;}
github.com
Sorry, I took yesterday late afternoon and evening off. I created: pauls_branch
linuxcapable.com
Yes and No... In the same way why does the SD library allow you access to SDFat?
Sometimes it is hard to find the right tradeoffs, as each of us may have different priorities for different things in their sketch. For example, someone who plugs in their Teensy to a PC to download their log files may want that done as fast as possible, as to not have to wait around for a long period of time, whereas someone else, may simply want to copy a new song to their jukebox app and not want it to interfere listening to their current music.
I think I might take a break from playing with MTP and play with some other things until the dust settles.
Start write file: test5busb.txt length:5000000000 Write Size:512
.................................................................
Time to write: 8012085
Start write packet indexed file: test5gn2.txt length:5000000000 Write Size:4096
0000000000 - ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789AB
0000000002 - ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789AB
...........................................................................................
Time to write: 1476255Thanks Paul.
bool mediaPresent() { return *this; }operator bool() {
// use of volatile prevents compiler from optimizing away
// re-reading the pointer if program repeated checks bool()
USBDrive *dev = *(USBDrive * volatile *)&device;
return dev != nullptr;
}As you said neuters mtp. Even more reason to stick with your large file branch for now. Spent a lot of time incorporating msc into mtp so definitely will be interesting to see any updates.