// the find
ioerror/libmsr
Reading, writing and analysis of magnetic stripe information
libmsr is a C library for talking to the MSR-206 magnetic stripe reader/writer over serial. It handles ISO and raw track formats, plus partial support for a couple of other readers. This is a niche hardware interfacing library for security researchers, transit card hobbyists, or anyone who needs to read/write mag stripe data without proprietary vendor software.
Clean separation of hardware backends into their own files (msr206.c, makstripe.c, audio.c) makes adding new devices tractable. Includes USB sniffing captures with commentary, which is genuinely useful for reverse engineering new hardware. Ships with practical utility programs (quick-clone, iso-dumper, raw-dumper) that double as real usage examples. Audio reader support via libsndfile is an interesting approach for cheap hardware access.
Abandoned in 2010 — 15+ years stale with 29 stars and no activity. Serial-only interface is a hard constraint; USB HID readers, which are what most people buy today, are not supported. No build system beyond a bare Makefile and no package distribution means setup is friction from the start. References a Google Code wiki that has been dead since 2016, so the hardware comparison chart and MAKStripe spec are gone.