PyPI · #5094 most downloaded on PyPI

pycdlib

1.21.0593K downloads/moclalancette/pycdlib ↗New releases in your daily digest, changelog included.

Pure python ISO manipulation library

Last release 9 days ago
25 Sep 2026
Release timing varies
gaps range from 2 months to 3.3 years
Nearly every release is documented
notes for 19 of 19 stable releases
Nothing withdrawn
no release was ever pulled
10 years old
19 releases · first in 2016

Release timeline

19 releases since 2016

20162018202020222024

Releases

1.21.025 Sept 2026
Signed-off-by: Chris Lalancette clalancette@gmail.com
Signed-off-by: Chris Lalancette clalancette@gmail.com
Open source →
1.20.05 Aug 2026
Signed-off-by: Chris Lalancette clalancette@gmail.com
Signed-off-by: Chris Lalancette clalancette@gmail.com
Open source →
Additional notes
Fix a couple of issues when adding in Rock Ridge Continuation Entries

Improve test coverage up to 98%

Make sure to reshuffle_extents() in get_file_byte_extents() if necessary so users get the actual ISO offset

Minor performance improvements when writing ISOs out

Big cleanup of the El Torito handling to be easier to read, more performant, and handle more cases gracefully

Clamp reads so that they can't be larger than the remaining size of the ISO and make huge virtual memory allocations

Support 512 and 1024 byte logical block sizes

Allow in-place modification by Rock Ridge, Joliet, or UDF path

In pycdlib-extract-files, ensure that a Rock Ridge ISO with symlinks can't write outside of the current directory

One column per quarter.

1.16.029 Apr 2026

Signed-off-by: Chris Lalancette clalancette@gmail.com

Open source →

Additional notes

Require Python 3.10+
Add support for parsing and writing UDF Extended File Entries
Add an optional encoding parameter to full_path_from_dirrecord so Shift-JIS and other non-UTF-8 ISOs can be walked
Fix modify_file_in_place corruption when the on-disk directory order differs from the in-memory sorted order
Fix on-disk extent ordering for files larger than 8.6 GB
Fix UDF reads of large files returning truncated data on UDF-bridge ISOs
Fix Rock Ridge version detection when 1.12 evidence lives only in the CE continuation block
Fix the second UDF anchor being written to an unreachable extent when a re-write shrinks the layout
Fix parsing of ISOs whose directory data_length is sub-extent-aligned (Windows install media, PS2 GT4)
Fix parsing of FreeBSD 14.3 ISOs by tightening XA-record detection
Fix a stale-position bug in PyCdlibIO when the underlying file descriptor is shared with other operations
Accept several non-compliant artifacts produced by VirtualBox (SP records outside the root, shared CE regions, NM records combining a name with the CURRENT / PARENT / HOST flag)
Reject overly long UDF filenames at entry-creation time with a clear error message instead of failing later in struct.pack
Improve the error message when Rock Ridge versions are inconsistent across an ISO
Treat an ISO with no Rock Ridge ER record as non-Rock-Ridge so callers using rr_path get a clear error at the API boundary
Several performance improvements in directory-record sorting, struct unpacking, dot-dot lookup, and UDF CRC computation

Open source →

1.15.025 Apr 2026

Signed-off-by: Chris Lalancette clalancette@gmail.com

Open source →

Additional notes

Remove Python 2 compatibility
Add an encoding parameter to the walk API so non-standard ISOs can be used
Fix ISOs that only have a single extent for Path Tables
Add the 'udf_path' argument to add_file so UDF ISOs can add paths
Fix timestamps for UDF

Open source →

1.14.014 Jan 2023

Signed-off-by: Chris Lalancette clalancette@openrobotics.org

Open source →

Additional notes

Fix Python 2 compatibility
Fix iteration over deep directories
Relax some error checking to allow non-standards-compliant ISOs to be read
Fix year rollover in the Australia timezone

Open source →

1.13.021 Jun 2022

Fix the use of inspect for modern Python 3

Fix the use of inspect for modern Python 3
Add in pycdlib-explorer functionality for modify-in-place
Add full support for Windows raw block devices
Fix UDF entries for large files
Allow some UDF errors to print a warning instead of throwing
Search for UDF anchors in additional locations
Fix UDF partition map parsing

Open source →

1.12.013 Aug 2021

Signed-off-by: Chris Lalancette clalancette@gmail.com

Open source →

Additional notes

Several fixes to work with raw Windows devices
Fix ISOs with missing Apple partition map entries
Relax restrictions on dates hundredthsofseconds
Fix MBR boot code sector size
More UDF cleanups

Open source →

1.11.08 Oct 2020

Add many more unit tests to get test coverage > 95%

Add many more unit tests to get test coverage > 95%
Preserve boot record contents when moving it
Make sure to allocate an extent for the boot_catalog in all cases
Fix deep directory depths with ISO level 4
Rewrite XA handling
Improve performance of filename checking
Add support for the AL record

Open source →

1.10.024 May 2020

Much improved IsoHybrid support for EFI/GTP

Much improved IsoHybrid support for EFI/GTP
Fix large, multi-extent files
Fix support for very large ISOs
Remove the unused and unloved pycdlib-compare tool
Fix ISO9660 date hundredths of second

Open source →

1.9.020 Dec 2019

Switch to read-only open by default for the open() call

Much improved support for UDF
Switch to read-only open by default for the open() call
Fixes to work on big-endian machines
APIs added:
- file_mode
APIs removed: None
APIs deprecated: None

Open source →

1.8.013 Aug 2019

Addition of "facades" for using PyCdlib in simpler ways

Addition of "facades" for using PyCdlib in simpler ways
Make iso_path optional for UDF when using add_symlink
Make iso_path optional when using rm_file()
Make iso_path optional when using add_fp()/add_file()
Create symlinks appropriately in pycdlib-extract-files
Fix copy_data on macOS
Support more of the UDF standard
Cleanup documentation
Allow UEFI El Torito identifier
Add an 'auto' mode for pycdlib-extract-files
Add an '-extract-to' option for pycdlib-extract-files
APIs added:
- get_iso9660_facade
- get_joliet_facade
- get_rock_ridge_facade
- get_udf_facade
- has_rockridge
- has_joliet
- has_udf
APIs removed: None
APIs deprecated: None

Open source →

1.7.028 Feb 2019

Add a tool to extract files with pycdlib

Better UDF compatibility
Add a tool to extract files with pycdlib
Greatly improve performance of pycdlib-genisoimage duplicate detection
Add a design document to the documentation
Better support for Rock Ridge SF records
Add type annotation to the entire codebase
Fix a bug with UDF directory sorting
Many more unit tests added
APIs added:
- walk()
- open_file_from_iso()
APIs removed: None
APIs deprecated: None

Open source →

1.6.029 Jul 2018

More fixes for better UDF compatibility

More fixes for better UDF compatibility
Internal revamp of UDF to move some functionality into the classes
Share more code internally
More tests
Better UDF support in pycdlib-explorer
More documentation, mostly in pycdlib-explorer
Python 3.4 compatibility
APIs added: None
APIs removed: None
APIs deprecated: None

Open source →

1.5.023 Jun 2018

Many more fixes for UDF compatibility

Many more fixes for UDF compatibility
Support for arbitrarily many hard-links between El Torito, Joliet, ISO9660, and UDF
Increase test coverage
Add support for duplicate file detection in pycdlib-genisoimage
Add support for Rock Ridge version 1.10
Fix up unicode handling of filenames
Minor performance optimizations
APIs added: None
APIs removed: None
APIs deprecated: None

Open source →

1.4.05 May 2018

Lots more updates to pycdlib-genisoimage

Lots more updates to pycdlib-genisoimage
Support for absolute Rock Ridge symlinks
Initial UDF support
Documentation updates
Performance optimizations
Increase test coverage
Deprecate a bunch of methods
Support ISOs that report incorrect PVD sizes
Initial UDF support
APIs added:
- get_file_from_iso()
- get_file_from_iso_fp()
- list_children()
- get_record()
- set_relocated_name()
APIs removed: None
APIs deprecated:
- get_and_write()
- get_and_write_fp()
- add_joliet_directory()
- rm_joliet_directory()
- list_dir()
- get_entry()

Open source →

1.3.220 Nov 2017

Switch to python3 for the tools

Switch to python3 for the tools
Small man page fixes
APIs added: None
APIs removed: None
APIs deprecated: None

Open source →

1.3.120 Nov 2017

Small fixes to fix up RPM packaging

Small fixes to fix up RPM packaging
APIs added: None
APIs removed: None
APIs deprecated: None

Open source →

1.3.020 Nov 2017

Support for Joliet levels 1, 2, and 3

Performance optimizations
Support for Joliet levels 1, 2, and 3
Very large file support (>4GB)
Increase test coverage
Add high-level documentation, hosted at https://clalancette.github.io/pycdlib/
Make API documentation available
APIs added:
- add_joliet_directory()
- rm_joliet_directory()
APIs removed: None
APIs deprecated: None

Open source →

1.0.026 Oct 2016

First stable release with API guarantees

First stable release with API guarantees
Rename library to PyCdlib to avoid name clashes
Many fixes to El Torito handling
Performance fixes
Compatibility fixes for ISO9660
Add an API to allow modifying files in place
More testing all over the tree
Add support for ISO9660 interchange level 4
Add support for "hard-links" between files
Add support for Rock Ridge 1.12
Dual Python2/Python3 support
APIs added:
- open_fp()
- get_and_write_fp()
- write_fp()
- add_file()
- modify_file_in_place()
- add_hard_link()
- rm_hard_link()
- add_isohybrid_fp()
- full_path_from_dirrecord()
- duplicate_pvd()
APIs removed:
- print_tree()
APIs deprecated: None

Open source →

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