zipc is a simple ZIP container “library” consisting of a C source file and
accompanying header file. The ZIP format is documented in the PKWARE
APPNOTE.TXT - .ZIP File Format Specification.
The current version implements reading and writing of files smaller than 4GB, with or without deflate compression. There is no support for signatures, encryption, password protection, etc. as those features of ZIP are typically not used for ZIP container-based formats.
I’m providing this as open source under the “new” 2-clause BSD license which allows you do pretty much do whatever you like with it. Please do provide feedback and report bugs to the Github project page so that everyone can benefit.