Expand description
Various byte or byte sequences used in the Telnet protocol.
Constants§
- Binary Transmission - https://datatracker.ietf.org/doc/rfc856/ In accordance with RFC856, this option specifies a way to indicate binary data should be transmitted across the connection. It allows the sender and receiver to negotiate and agree upon the data transfer mode to use during a Telnet session.
- RFC 1572: Telnet Environment Option https://datatracker.ietf.org/doc/html/rfc1572 Negotiate About Environment Variables: Telnet option
ENV_ACCT: Represents the “Acct” or “Account” environment variable in accordance with RFC1572. This is used for the account id the client wishes to use.ENV_DISPLAY: Represents the “Display” environment variable in accordance with RFC1572. This is used to convey information about the user’s display environment, similar to the DISPLAY environment variable in Unix-like systems.- Indicates the data following it should be inserted into the data stream as is.
- Environment variable change notification
- Environment variable definition
ENV_JOB: Represents the “Job” or “Jobname” environment variable in accordance with RFC1572. This is used to pass the id of the job (process, service) the user wants to use.ENV_PRINTER: Represents the “Printer” environment variable in accordance with RFC1572. This is used to specify the default location for printer output- Request to send environment variables
ENV_SYSTEMTYPE: Represents the “SystemType” environment variable in accordance with RFC1572. This variable identifies the type of operating system of the client.ENV_USER: Represents the “User” environment variable in accordance with RFC1572. This is typically used to identify the user on the remote system.- User-defined variable
- Value of variable
- Environment variable
- Represents a mask used in LINEMODE negotiations to indicate the forwarding of linemode options. When set, this mask signals that the client wishes to forward linemode options to the server, thereby enabling the server to configure linemode settings. This capability is part of the LINEMODE suboptions negotiation, allowing for dynamic and flexible configuration of line processing behaviors based on the client’s requirements and capabilities.
- Defines the suboption code for the LINEMODE SLC (Special Character) function. This is used in Telnet communications to negotiate the handling of special characters that control various terminal functions, such as interrupt, flush, and suspend actions. The SLC suboption allows for the configuration and manipulation of these special characters, enhancing the control over the terminal behavior in a Telnet session.
- Remote flow control - https://datatracker.ietf.org/doc/rfc1372/
- SLC_ABORT: Abort
- SLC_ABORTC: Abort Output Character
SLC_ACK: A flag used to acknowledge the receipt or acceptance of an SLC function setting. This acknowledgment can be part of a negotiation process where one side proposes a setting and the other side acknowledges it.- SLC_AO: Abort Output
- SLC_AYT: Are You There
- SLC_BRK: Break
- SLC_BRKC: Break Character
SLC_CANTCHANGE: Indicates that the current SLC function’s setting cannot be modified. This level is used for SLC functions that are essential for the operation or for which the ability to change the setting would result in undesired behavior.- Constants representing different levels and functionalities associated with Telnet’s Special Linemode Characters (SLC).
SLC_DEFAULT: Represents the default state of a linemode option. This level indicates that the default action should be taken for a particular SLC function. It is typically used when no specific action or value is assigned to an SLC function. - SLC_DSUSPC: Delayed Suspend Current Process
- SLC_EC: Erase Character
- SLC_EL: Erase Line
- SLC_EOF: End of File
- SLC_EOFCHAR: End of File Character
- SLC_EOR: End of Record
- SLC_EORC: End of Record Character
- SLC_EW: Erase Word
- SLC_EXIT: Exit
SLC_FLUSHIN: A flag indicating that all incoming data should be flushed (i.e., discarded). This is used in situations where it is necessary to clear the input buffer, such as when the mode of operation changes or in response to certain error conditions.SLC_FLUSHOUT: Similar toSLC_FLUSHIN, but for outgoing data. This flag indicates that all data queued for output should be flushed. This can be useful in situations where an immediate response is needed, or when clearing the output buffer is required to maintain the correct sequence of data or commands.- SLC_FORW1: Forward Character
- SLC_FORW2: Forward Line
- SLC_IP: Interrupt Process
SLC_LEVELBITS: A mask used to isolate the level bits in an SLC function definition. This constant is used in operations that require identifying the specific level associated with an SLC function.- SLC_LNEXT: Literal Next
- SLC_LP: Local Print
- SLC_MCL: Move Cursor Left
- SLC_MCR: Move Cursor Right
- SLC_MCUB: Move Cursor Up One Line
- SLC_MCUF: Move Cursor Down One Line
- SLC_MCWL: Move Cursor Word Left
- SLC_MCWR: Move Cursor Word Right
SLC_NOSUPPORT: Represents the lack of support for a particular SLC function. This level is used when a Telnet client or server does not recognize or cannot implement the specific SLC function being queried or set.- SLC_REPRINT: Reprint Unread Input
- SLC_RP: Repaint
- SLC_SUSP: Suspend Process
- SLC_SUSPC: Suspend Current Process
- SLC_SUSPCHAR: Suspend Process Character
- Telnet Special Linemode Characters (SLC) Functions as Constants SLC_SYNCH: Synchronize
SLC_VALUE: Signifies that a specific value is associated with an SLC function. This level is used when a particular SLC function is configured with a specific, non-default value that must be recognized and acted upon.- SLC_XOFF: Stop Transmission
- SLC_XOFFC: XOFF Character
- SLC_XON: Resume Transmission
- SLC_XONC: XON Character
- STATUS - Verify the current status of options - https://www.rfc-editor.org/rfc/rfc859.html
- TIMING MARK - Verify that requested information has been used - https://datatracker.ietf.org/doc/rfc860/