| 释义 |
flag 1. A marker or indicator of a condition, such as an error condition, in a program or file. See also file and program. 2. In Synchronous Data Link Control (SDLC), High-level Data Link Control (HDLC), and other frame-based communications protocols, a specific eight-bit pattern that alerts the receiving device to the beginning or end of a frame, i.e., message unit.The most commonly used flag character is 01111110 in binary code (7E in hexadecimal). Flags also fill all idle time on the line between frames. Only one flag is needed between frames. See also frame, HDLC, hexadecimal notation, protocol, and SDLC. |