SIGTTIN (21)SIGTTIN (21) — Background Read from Terminal
A background process attempted to read from its controlling terminal.
EBADFA file descriptor argument is not a valid open file descriptor or is not open for the requested operation.
The program attempted to use a file descriptor that was never opened, has already been closed, or is not open in the correct mode. Double-closing a file descriptor or using one after a failed open() call are common causes.
Ensure file descriptors are valid before use. Check the return value of open() and socket() calls. Avoid using a file descriptor after calling close() on it. Use strace to trace file descriptor operations.
SIGTTIN (21)A background process attempted to read from its controlling terminal.
SIGILL (4)The process attempted to execute an illegal, malformed, or privileged machine instruction.
EPIPEA write was attempted on a pipe or socket for which the reading end has been closed.
EFAULTAn invalid memory address was passed to a system call as an argument.
SIGURG (23)Urgent or out-of-band data arrived on a socket.
EMFILEThe per-process limit on the number of open file descriptors has been reached.