Corrupted files after copy reget #5138

Is there an existing issue for this?

• I have searched the existing issues

Midnight Commander version and build configuration

GNU Midnight Commander 4.8.33
Built with GLib 2.84.3
Built with S-Lang 2.3.3 with terminfo database
With builtin editor
With subshell support as default
With support for background operations
With mouse support on xterm
With internationalization support
With multiple codepages support
With ext2fs attributes support
Virtual File Systems:
 cpiofs, tarfs, sfs, extfs, ext2undelfs, ftpfs, shell
Data types:
 char: 8; int: 32; long: 64; void *: 64; size_t: 64; off_t: 64; uintmax_t: 64;

Operating system

Linux blumenoid 6.18.12-gentoo #3 SMP PREEMPT_DYNAMIC Fri May  1 18:25:04 CEST 2026 x86_64 AMD Ryzen 7 7800X3D 8-Core Processor AuthenticAMD GNU/Linux

Is this issue reproducible using the latest version of Midnight Commander?

• I confirm the issue is still reproducible with the latest version of Midnight Commander

How to reproduce

1. Take a bunch of big files, start copying the first one
2. Abort during the copying process, choose Keep
3. Select multiple files, starting with the one that was partially copied
4. Start copying again. Choose Reget to append the rest of the first file

Expected behavior

All files should copy, first one should finish, the rest should be copied normally. Source and destination files should be exactly the same.

Actual behavior

After copying is finished the first file is the only one that matches the source. Every other file is shorter by the partial length of the first file when copying was aborted. All files were copied starting from the same offset as the first one.

Additional context

Serious data corruption, especially when copying disk images and not checking file lengths / checksums