RT-Thread RTOS is a real-time operating system for 16-bit to 32-bit microcontrollers, with components which include a hard real-time kernel, a command line shell, a device virtual file system, and a graphic user interface. RT-Thread/GUI is a graphic user interface integrated with RT-Thread. It provides a multi-window, multi-thread graphic user interface. Rich widgets are implemented in RT-Thread/GUI, such as label, button, checkbox, textbox, etc. The typical RAM usage of RT-Thread/GUI is less than 20kB RAM.
ptee is a Unix shell tool similar to tee, but it allows you to invoke multiple sub-shells in parallel. Standard input to ptee is copied to both normal standard output and to each sub-shell running under ptee. Each sub-command is run concurrently and fed the same input. The output of each sub-command is thrown away, but any shell expression can be used, such as redirecting to a file. Note that there are some limits on ptee. The shell pipeline will only execute at the pace of the slowest sub-command; otherwise large amounts of data would have to be buffered. Also, the shell that ptee invokes requires 'sh'-like semantics, such as supporting the -c option.
The KornShell language is an interactive command language that provides access to the Unix system and to many other systems, on the many different computer systems on which it is implemented. The KornShell language is also a complete, powerful, high-level programming language for writing applications, often more easily and quickly than with other high-level languages. This makes it especially suitable for prototyping. There are two other widely used shells, the Bourne shell developed by Steven Bourne at AT&T Bell Laboratories, and the C shell developed by Bill Joy at the University of California. ksh has the best features of both, plus many new features of its own. Thus ksh can do much to enhance your productivity and the quality of your work, both in interacting with the system, and in programming. ksh programs are easier to write, and are more concise and readable than programs written in a lower level language such as C.
The STX ExecPipe library provides a convenient C++ interface to execute child programs connected via pipes. It is a front-end to the system calls fork(), pipe(), select(), and execv() and hides all the complexity of these low-level functions. It allows a program to build a sequence of connected children programs with the input and output of the pipe sequence redirected to a file, string, or file descriptor. The library also allows custom asynchronous data processing classes to be inserted into the pipe or placed at the source or sink of the sequence.