Serial Line Sniffer 0.4.4 review

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slsnif is a serial line sniffer

License: GPL (GNU General Public License)
File size: 147K
Developer: Yan Gurtovoy
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slsnif is a serial line sniffer. It listens to the specified serial port and logs all data coming through it. slsnif works transparently for both the device connected to the serial port and the controlling software for this device. It operates by opening a pseudo tty (pty) and linking it to the actual serial port.

slsnif operates by opening a pty and linking it to the serial port. These are following parameters / options:

1. Serial port to open (required).
2. Name of the file to direct output to (optional, defaults to stdout).
3. Desired baudrate (optional, defaults to 9600 baud).
4. Timestamp On/Off (optional, defaults to Off).
5. Print ascii values in hex On/Off (optional, defaults to Off)
6. Print number of bytes transmitted On/Off (optional, defaults to Off).
7. Optional colors for timestamp, number of bytes transmitted and normal output.
8. Lock port On/Off (optional, defaults to On).
9. Use Unix98 ptys instead of BSD ptys (optional, defaults to BSD style).
10. Second serial port to open. If specified, this port will be used instead of a pty, thus providing an ability to log data between two serial ports.

What's New in This Release:
Added ability to resynchronize ports at any time by sending a SIGUSR1 signal to slsnif. Useful for debugging applications that change port parameters mid-way, after starting the transmission. One example is pppd daemon, which sets initial parameters in the chat script, and changes them later, after chat script terminates.
Added ability to use SYSV (Unix98) ptys instead of BSD ones (see '-u' and '--unix98' parameters). This option can also be turned on/off from rc-file.

Serial Line Sniffer 0.4.4 keywords