ANSI-CIO is a set of transparent replacements for the file functions in stdio.h and unistd.h. They offer the ability to share file accesses, and to open, read, write (and more) files concurrently. Using these functions it is possible to open a file more often than only once and to access it. All functions are completely compatible with their ANSI counterparts.
The ATLAS (Automatically Tuned Linear Algebra Software) project is an ongoing research effort focusing on applying empirical techniques in order to provide portable performance. It provides C and Fortran77 interfaces to a portably efficient BLAS implementation, as well as a few routines from LAPACK.
This data structure features fast (O(log N)) insertion, removal, and retrieval of records, provided that there is a sorting relation over their keys and there are no entries with equal keys. The AVL tree is an explicit binary searching tree, where left children of each vertex are less or equal, while right children are greater or equal than the vertex itself. In addition, the tree is balanced so that the difference between the depths of the two subtrees of each vertex is at most one.