Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
Anyone knows why the “ÿôÿý” string appears in various logs on Linux? I cannot figure it out. It does not appear every time, but when it does it makes the log (oracle backup log for example) difficult to read.
Any help/hint will be much appreciated!
It looks like a telnet command sequence that was intended to be interpreted as a command by some communications software, but for some reason got passed through as ordinary characters rather than being interpreted as a telnet command.
All telnet commands start with the byte 0xff followed by another byte identifying the command. 0xff will display as ÿ in ISO Latin-1. 0xff 0xf4 (ÿô) is a telnet Interrupt Process command, which should send a SIGINT signal to the process (like ^C). 0xff 0xfd (ÿý) is the beginning of a telnet DO command, used to negotiate turning on some telnet option; it should be followed by another byte identifying the specific option (although it may be a non-printing control character).