Peter MacDonald (computer programmer) the Linux Kernel into Dynamically Loadable Modules"). MacDonald co-developed early features of the Linux kernel in the early 1990s, including shared libraries, pseudo terminals, the select call and virtual consoles. He announced Softlanding Linux System (SLS), the first standalone Linux install, for testing in August 1992 (on 15 floppy disks), and for general release in October 1992 (recommending at least 10 MB of disk space). SLS became popular, but also drew criticism. MacDonald was criticized for trying to make money on free software, but defended by Linus Torvalds. Two of the early Linux distributions were made specifically in reaction to
FLEX (operating system) increased disk reliability at the expense of compatibility and speed. Later, TSC introduced the multitasking, multi-user, Unix-like UniFLEX operating system, which required DMA disk controllers, 8" disk, and so sold in only small numbers. Several of the TSC computer languages were ported to UniFLEX. During the early 1980s, FLEX was offered by Compusense Ltd as an operating system for the 6809-based Dragon 64 home computer. FLEX (operating system) The FLEX single-tasking operating system was developed by Technical Systems Consultants (TSC) of West Lafayette, Indiana, for the Motorola 6800 in 1976. The original version was for 8" floppy disks and the