Is a socket a file?
Is a socket a file?
Socket. A socket is a special file used for inter-process communication, which enables communication between two processes. In addition to sending data, processes can send file descriptors across a Unix domain socket connection using the sendmsg() and recvmsg() system calls.
What type is a file descriptor?
A file descriptor is an unsigned integer used by a process to identify an open file. The number of file descriptors available to a process is limited by the /OPEN_MAX control in the sys/limits. h file. The number of file descriptors is also controlled by the ulimit -n flag.
Which are 3 standard files of descriptor?
Stdin, stdout, and stderr On a Unix-like operating system, the first three file descriptors, by default, are STDIN (standard input), STDOUT (standard output), and STDERR (standard error). The default data stream for input, for example in a command pipeline.
What does a socket descriptor do?
Each socket within the network has a unique name associated with it called a socket descriptor—a fullword integer that designates a socket and allows application programs to refer to it when needed.
What is socket descriptor in Unix?
In Unix and Unix-like computer operating systems, a file descriptor (FD, less frequently fildes) is a unique identifier (handle) for a file or other input/output resource, such as a pipe or network socket.
What file descriptor is Stdin?
File descriptor
| Integer value | Name | file stream |
|---|---|---|
| 0 | Standard input | stdin |
| 1 | Standard output | stdout |
| 2 | Standard error | stderr |
What is bad file descriptor?
“Bad file descriptor” means that we tried to perform an operation on a file descriptor which is not active, probably closed beneath someone’s feet. There is no file path associated with it anymore.
Can a socket file descriptor be zero?
file descriptor 0 is always stdin.