Where is it defined that "." denotes the current working directory? Does the C language understand this convention? The answer is no—C's chdir() function simply passes the string to the chdir system call. It is the kernel that interprets "." as the current working directory

"C is a high level language based on an earlier language called B...It is designed to run under the Unix operating system (also designed and written by these people)" BYTE from Oct 1977 introduced readers to the C programming language

The traditional Unix shells are all written in C (bash, dash, zsh, ksh, tcsh). However: xonsh — written in Python, Elvish — written in Go, Oil Shell — mostly Python, Nushell — written in Rust.

FORTRAN doesn't have fork() or exec() natively. Creating a new process in FORTRAN requires either using system() function (portable but limited) or calling C functions via ISO_C_BINDING (allowing full control). Modern FORTRAN (2003 and later) allows calling C functions directly

The Commodore 900, developed in West Germany, debuted at the Hanover Fair in 1985. It ran a customised version of Coherent, an early Unix clone from Mark Williams Company. The computer never shipped, and it was cancelled when Commodore bought Amiga

Mark Williams Company was a failed paint producer, and the owner reused the corporate shell for a new software venture. The company produced Coherent, an impressive Unix clone, and one of the one of the earliest UNIX-like implementations for x86, in 1984-5 targeting i286/i386 PCs

Coherent was so good that AT&T asked Dennis Ritchie to investigate its implementation for possible UNIX code infringements. x.com/unix_byte/stat…

In the bash source code, there is a “nofork” condition, which causes bash not to fork a child before executing a program. But why would bash want to execute a program without forking first? This is used by the bash exec built-in, which skips forking and calls execve() directly

Therefore, running $ exec /bin/ls will replace the shell with `ls`, causing the the shell to instantly disappear. x.com/unix_byte/stat…

Stephen R. Bourne, known for the Bourne shell (sh), also wrote the original "Advanced Debugger" (adb) at Bell Labs for Version 6 Unix (1975). The prominent successors of adb are Sun's dbx and the GNU Debugger (GDB), now de facto standard on Linux.

PVM (Parallel Virtual Machine) was an academic project that enabled concurrent computing over heterogeneous networked computers. The idea was to create a virtual computer from multiple idle workstations, i.e. a "poor man's supercomputer". XPVM was a GUI monitor for the PVM.

Flame wars from 1982: "I have never even seen an advertisement for a programmer with Unix or C experience"

In August 1988, BYTE featured an article by Brian Kernighan and Dennis Ritchie on the state of C, followed by Bjarne Stroustrup’s article “A Better C?”, introducing C++.