tcgetsid - Returns the session ID of the terminal
Standard C Library (libc.so, libc.a)
Interfaces documented on this reference page conform to industry standards as follows:
Refer to the standards(5) reference page for more information about industry standards and associated tags.
Specifies a terminal.
The tcgetsid routine is a part of the general terminal interface. This routine obtains the session ID of the terminal as specified by the fildes parameter.
On success, the tcgetsid returns the session ID that is associated with the terminal specified. If the session ID of the terminal cannot be obtained, a value of (pid_t)-1 is returned and errno is set to indicate error.
The tcgetsid() function sets errno to the specified values for the following conditions: The descriptor fildes is not associated with a controlling terminal. The descriptor fildes is not valid. [XPG4-UNIX] The file associated with fildes is not a terminal.
Standards: standards(5) delim off