Socat

serial
https://superuser.com/questions/771155/impersonate-a-serial-device-with-socat?rq=1

usb
https://www.lucid-control.com/accessing-usb-io-module-network-linux-socat/ connect network port to usb https://jamesthom.as/2021/01/virtual-serial-ports-using-socat/ https://serverfault.com/questions/453032/socat-to-share-a-serial-link-between-multiple-processes?rq=1. serial between multiple processes, pipes socat to socat https://serverfault.com/questions/360321/forwarding-linux-terminal-from-serial-port-to-tcp-with-socat?rq=1 https://serverfault.com/questions/154573/serial-port-forwarding-over-tcp-ip-linux-server?rq=1 https://serverfault.com/questions/384741/forwarding-serial-port-over-network-and-back-to-serial-char-device-on-remote-hos?rq=1 https://www.domoticz.com/wiki/SharingSerialDevices WIKI https://stackoverflow.com/questions/35998803/pppd-over-socat-using-interface-option?rq=1 for realpath of symlink for direct path https://stackoverflow.com/questions/5890505/socat-tunnel-ip-through-tty?rq=1

https://stackoverflow.com/questions/27837627/ip-tunnel-over-linux-serial-default-shell?noredirect=1&lq=1

server
https://serverfault.com/questions/693089/socat-tcp-file-server https://serverfault.com/questions/246347/whats-the-difference-between-socat-and-netcat?rq=1 https://serverfault.com/questions/346481/echo-server-with-netcat-or-socat?rq=1 https://serverfault.com/questions/414350/access-d-bus-remotely-using-socat?rq=1 https://serverfault.com/questions/405518/how-to-configure-d-bus-and-ssh-x-forwarding-to-prevent-ssh-from-hanging-on-exit?rq=1 https://serverfault.com/questions/768942/socat-create-returning-bad-file-descriptor?rq=1 https://serverfault.com/questions/655715/always-keep-socat-alive?rq=1

netcat
https://serverfault.com/questions/651979/how-to-redirect-a-udp-response-with-netcat?rq=1 https://serverfault.com/questions/207683/listen-to-udp-data-on-local-port-with-netcat?rq=1 https://serverfault.com/questions/457433/proxy-with-netcat-forever?rq=1 https://serverfault.com/questions/959699/ssh-connection-using-proxy-instead-of-port-forwarding?rq=1

proxy
https://serverfault.com/questions/254855/socat-connect-connect-proxy-two-inbound-tcp-connections-to-expose-a-firewalled https://gist.github.com/lene/a517e635de86e73f6a981b0b584fb68a ssh over tor with socks4

socks5
https://github.com/runsisi/socat fork of socat with socks5 support

mkfifo
https://unix.stackexchange.com/questions/195880/socat-duplicate-stdin-to-each-connected-client refs https://stackoverflow.com/questions/17480967/using-socat-to-multiplex-incoming-tcp-connection https://gist.github.com/mathieue/3505472 udp multicase --- https://stackoverflow.com/questions/28032549/socat-terminates-after-connection-close?rq=1 https://stackoverflow.com/questions/36575588/socat-not-closing-tcp-connection?rq=1

terminals
https://superuser.com/questions/1100342/socat-and-rich-terminal-again?noredirect=1&lq=1 from https://superuser.com/questions/123790/socat-and-rich-terminals-with-ctrlc-ctrlz-ctrld-propagation Signals nor tty ownership cannot be 'magically' carried over a socket. Over AF_UNIX, you could send the tty file descriptor itself (using sendmsg and recvmsg) and have the receiving side use it (and not the socket) as the subprocess' stdout/stderr. This cannot be done with plain socat, but this method is used internally by e.g. the tmux tool. ssh https://github.com/darkk/redsocks https://github.com/vi/tcpsocks https://github.com/vi/websocat Proxy TCP connections to WebSocket connections and back.

tor
https://superuser.com/questions/615140/ssh-tunnel-with-socat-and-tor?rq=1 torsocks

system
https://stackoverflow.com/questions/1697440/difference-between-system-and-exec-in-linux system calls out to sh to handle your command line, so you can get wildcard expansion, etc. exec and its friends replace the current process image with a new process image. With system, your program continues running and you get back some status about the external command you called. With exec, your process is obliterated. In general, I guess you could think of system as a higher-level interface. You could duplicate its functionality yourself using some combination fork, exec, and wait. To answer your final question, system causes a child process to be created, and the exec family do not. You would need to use fork for that. The exec function replace the currently running process image when successful, no child is created (unless you do that yourself previously with fork). The system function does fork a child process and returns when the command supplied is finished executing or an error occurs. Refs UNIX Systems Programming for SVR4, David Curry https://man7.org/linux/man-pages/man3/system.3p.html

gists

 * 1) https://gist.github.com/cfra/752d6e761225fd5bf783b44abe30f707#file-ethernet-socat-ssh-md
 * 2) https://gist.github.com/lene/a517e635de86e73f6a981b0b584fb68a socat socks4 over tor

links
https://www.pentestpartners.com/security-blog/socat-fu-lesson, (https://archive.ph/Zhe1u) uses netsed

http://www.dest-unreach.org/socat/doc/socat.html  MAN page

https://copyconstruct.medium.com/nonblocking-i-o-99948ad7c957 by Cindy Sridharan https://copyconstruct.medium.com/socat-29453e9fc8a6 fd  by Cindy Sridharan https://gist.github.com/ntamas/591513 copy file to dropbox ,uses socat https://stackoverflow.com/questions/16956810/how-to-find-all-files-containing-specific-text-string-on-linux?rq=1
 * 1) https://github.com/positron-solutions/unixsocks Want to ssh over a tor service but socat doesn't accept unix addresses and you've configured your tor client to serve local clients over a unix socket? This is your tool
 * 2) http://www.dest-unreach.org/socat/doc/linuxwochen2007-socat.pdf
 * 3) http://www.dest-unreach.org/socat/doc/
 * 4) https://github.com/freelan-developers/freelan and http://www.freelan.org/ VPN client
 * 5) http://www.pocketnix.org/posts/Linux%20Networking:%20MAC%20VLANs%20and%20Virtual%20Ethernets
 * 6) https://www.redhat.com/sysadmin/getting-started-socat
 * 7) https://www.linux.com/news/socat-general-bidirectional-pipe-handler/ VPN with single line
 * 8) https://github.com/craSH/socat/blob/master/EXAMPLES

pentesting
https://gist.github.com/opnchaudhary/3731935 yum repositories https://gist.github.com/denji/84b7b6a07b318ca89919 penetration testing cheat sheet

ssh posix