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+Title: Reduce floppy disk size after formatting
+Author: rodarima
+Created: Sat, 29 Jun 2024 14:40:21 +0000
+State: closed
+
+The useful space to store files inside a floppy is less than the capacity of the floppy itself:
+```
+  % mkfs.msdos -C floppy.img 1440
+  mkfs.fat 4.2 (2021-01-31)
+  % stat -c %s floppy.img
+  1474560
+  % mkdir floppy
+  % sudo mount -o loop,uid=$USER floppy.img floppy
+  % dd if=/dev/zero bs=1 count=100M of=floppy/test
+  dd: error writing 'floppy/test': No space left on device
+  1457665+0 records in
+  1457664+0 records out
+  1457664 bytes (1,5 MB, 1,4 MiB) copied, 0,912079 s, 1,6 MB/s
+  % echo $((1474560 - 1457664))
+  16896
+```
+It needs a bit more than 16K to store the FAT table, so round it to 32K to allow some clearance for changes in FAT header size.
+```
+  % echo $((1474560 - 32*1024))
+  1441792
+```
+\ No newline at end of file