Kyle Ambroff-Kao 0329a37271 Userland: Handle terminal window resizing in less(1)
Before this patch less would query the terminal geometry only at
startup and use this information to render the file when
appropriate. If the terminal is resized then the output is broken in
several different ways because of this.

This patch adds a SIGWINCH signal handler receive notification any
time the terminal is resized. This signal handler just sets a flag to
notify the main loop that a resize has occurred.

The main loop of the program just calls get_key_sequence() to get
input from the user, interpreting keystrokes as commands like scroll
up or down. The get_key_sequence() function has been changed to return
Optional<String>, so it either returns a keystroke from the user or it
returns nothing as an empty Optional.

While the user is not pressing any keys on the keyboard, the program
is blocking on a read() system call in get_key_sequence(). When
SIGWINCH is received, this read() will return with -1 and errno is set
to EINTR since the system call was interrupted by the signal. When
this happens we just return an empty Optional.

The mainloop now checks to see if a resize has been requested by
checking the flag, and if it has it performs a resize.

init() now just calls resize() since the required logic is the same.

Setters for m_filename and m_prompt are removed because these are now
just initialized by the constructor, as they never change for the life
of the program.
2021-10-31 12:34:37 +01:00
2021-10-31 11:52:27 +01:00
2021-10-04 12:03:53 +01:00

SerenityOS

Graphical Unix-like operating system for x86 computers.

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About

SerenityOS is a love letter to '90s user interfaces with a custom Unix-like core. It flatters with sincerity by stealing beautiful ideas from various other systems.

Roughly speaking, the goal is a marriage between the aesthetic of late-1990s productivity software and the power-user accessibility of late-2000s *nix. This is a system by us, for us, based on the things we like.

I (Andreas) regularly post raw hacking sessions and demos on my YouTube channel.

Sometimes I write about the system on my github.io blog.

I'm also on Patreon and GitHub Sponsors if you would like to show some support that way.

Screenshot

Screenshot as of b36968c.png

Kernel features

  • x86 (32-bit) and x86_64 (64-bit) kernel with pre-emptive multi-threading
  • Hardware protections (SMEP, SMAP, UMIP, NX, WP, TSD, ...)
  • IPv4 stack with ARP, TCP, UDP and ICMP protocols
  • ext2 filesystem
  • POSIX signals
  • Purgeable memory
  • /proc filesystem
  • Pseudoterminals (with /dev/pts filesystem)
  • Filesystem notifications
  • CPU and memory profiling
  • SoundBlaster 16 driver
  • VMWare/QEMU mouse integration

System services

  • Launch/session daemon (SystemServer)
  • Compositing window server (WindowServer)
  • Text console manager (TTYServer)
  • DNS client (LookupServer)
  • Network protocols server (RequestServer and WebSocket)
  • Software-mixing sound daemon (AudioServer)
  • Desktop notifications (NotificationServer)
  • HTTP server (WebServer)
  • Telnet server (TelnetServer)
  • DHCP client (DHCPClient)

Libraries

  • C++ templates and containers (AK)
  • Event loop and utilities (LibCore)
  • 2D graphics library (LibGfx)
  • OpenGL 1.x compatible library (LibGL)
  • GUI toolkit (LibGUI)
  • Cross-process communication library (LibIPC)
  • HTML/CSS engine (LibWeb)
  • JavaScript engine (LibJS)
  • Markdown (LibMarkdown)
  • Audio (LibAudio)
  • Digital Signal Processing/Synthesizer Chains (LibDSP)
  • PCI database (LibPCIDB)
  • Terminal emulation (LibVT)
  • Out-of-process network protocol I/O (LibProtocol)
  • Mathematical functions (LibM)
  • ELF file handling (LibELF)
  • POSIX threading (LibPthread)
  • Higher-level threading (LibThreading)
  • Transport Layer Security (LibTLS)
  • HTTP and HTTPS (LibHTTP)
  • IMAP (LibIMAP)

Userland features

  • Unix-like libc and userland
  • Shell with pipes and I/O redirection
  • On-line help system (both terminal and GUI variants)
  • Web browser (Browser)
  • C++ IDE (HackStudio)
  • Desktop synthesizer (Piano)
  • E-mail client (Mail)
  • Various desktop apps & games
  • Color themes

How do I read the documentation?

Man pages are available online at man.serenityos.org. These pages are generated from the Markdown source files in Base/usr/share/man and updated automatically.

When running SerenityOS you can use man for the terminal interface, or help for the GUI.

How do I build and run this?

See the SerenityOS build instructions

Before opening an issue

Please see the issue policy.

FAQ: Frequently Asked Questions

Get in touch

Join our Discord server: SerenityOS Discord

Author

Contributors

(And many more!) The people listed above have landed more than 100 commits in the project. :^)

License

SerenityOS is licensed under a 2-clause BSD license.

Description
No description provided
Readme BSD-2-Clause 280 MiB
Languages
C++ 66.2%
HTML 21.5%
JavaScript 10%
CMake 0.7%
Objective-C++ 0.5%
Other 1%