Jul 29, 2017 · Keyboard set to "cat mode" Ask Question Asked 7 years, 7 months ago. Modified 4 years, 7 months ago.

How to "cat and follow" a file, i.e. output content of the file to stdout, but don't exit on EOF, instead keep subsribed to that file and continue outputting new portions of the data, exiting only if the file is closed by writer and not re-opened within N seconds.

Feb 15, 2021 · Is there a command to output a large file and follow on directly in the shell stdout? I am aware of less +F or I could simply use tail with an ultimately high n like tail -f -n1000000 if the file is

I wrote a shell script that uses cat and tr commands to generate a file. My shell script looks like #!/bin/bash printf "generating random file > plaintext \n" cat -v | tr "a-z" "b-y" < plaintext > generatedtext On executing the script, it doesn't terminate the cat command and when I've CTRL + Z to stop the shell script

Aug 10, 2017 · cat /dev/ttyS0 Or: cat < /dev/ttyS0 The first example is an app that opens the serial port and relays what it reads from it to its stdout (your console). The second is the shell directing the serial port traffic to any app that you like; this particular app then just relays its …

Jan 1, 2015 · Runaway cat commands were always a problem when a long ASCII file was dumped at the slow output device and the the entire file placed in the device driver output buffer. Ctrl-O would start the flush of the buffer and a follow up Ctrl-O would toggle off the flush so the cat could be read at normal speed.

Jun 4, 2019 · nb: that trick still relies on all the other writers to close the pipe in order for the cat to return. If another process has opened the pipe with eg. exec 7>fifo and keeps the fd 7 open, the cat <>fifo <fifo will still block, but not when trying to open the pipe, but when trying to …

May 10, 2016 · cat doesn't do that; all cat does is write bytes to the standard output (unless you're using the "harmful" options). The terminal program (and/or the terminal hardware, if applicable, i.e., its firmware) determines how to render bytes as characters, possibly with an …

No: if you cat to a terminal, because it (the terminal software) is sending the output to your screen, or interpreting control sequences (it is emulating an old piece of hardware, e.g., a teletype device). but: Yes: if you cat to a pipe and the program receiving can interpret the characters as commands. Look at this for example:

Sep 7, 2021 · In generate mode, ddrescue does not know how the image file came about (by ddrescue, by dd, by something else), so it makes the assumption that any binary zero area might have been skipped over previously. So if you have areas with all-zero data on your disk, it might attempt to re-read those, and only skip over areas that have non-zero data.