SIGHUP: This signaled the end user terminal, usually at the end of the process control terminal, inform each job during the same session, then they are not associated with the control terminal. For example, when you log on Linux, the system will automatically assign a user to log in to control terminal, all programs run in this terminal, including the foreground and background process group, generally belong to the same session. When the user exits, all the process groups will receive the signals, the default action for this signal is to terminate the process. In addition to the terminal from the daemon relations, this signal is used to inform it to reread its configuration file.
SIGINT: Program termination signal. Notice foreground process group to terminate the process when the user presses CRTL + C.
SIGQUIT: Ctrl + \ control, process receives a core file is generated when the exit signal, similar to a program error signal.
SIGILL: execute an illegal instruction. Usually because the executable itself an error, or the data segment, it is also possible to generate a stack overflow when this signal.
SIGTRAP: breakpoint instruction is generated by a stuck or other instructions used by the debugger.
SIGABRT: call abort function generates, will make the program ends abnormally.
SIGBUS: illegal address. Including memory address alignment error. Such as access to a four-word integer, but the address is not a multiple of 4. It differs from SIGSEGV is that the latter is due to the unauthorized access to the legal address of the trigger.
SIGFPE: arithmetic fatal error occurred.
SIGKILL: for an immediate end to run the program.
SIGUSR1: left to the user, the user can customize.
SIGSEGV: Access is not assigned to the user memory area. Or operating area without permission.
SIGUSR2: left to the user, the user can customize.
SIGPIPE: pipe rupture signal. When the execution pipeline to generate a reading process is already running end of the write operation.
SIGALRM: a clock timing signal. Generated when the alarm function is terminated by the time set.
SIGTERM: End of program signals. shell generated using the kill signal, when not the end of the process, try to use SIGKILL signal.
SIGSTKFLT: Stack error.
SIGCHLD: End child process, the parent will receive. If the child process ends when the parent does not wait for the signal processing or not, the child will become a zombie process.
SIGCONT: make a stop in the process to continue.
SIGSTOP: stop the process of implementation. Suspended.
SIGTSTP: stop running, can be ignored. Ctrl + z.
SIGTTIN: When a background process needs to receive data from the terminal, all processes will receive the signal, suspended.
SIGTTOU: SIGTTIN with similar, but generated when the write terminal.
SIGURG: generating an emergency on the socket.
SIGXCPU: signal is generated when the CPU time limit exceeded.
SIGXFSZ: When the process of trying to expand a file that is generated when the file size exceeds the resource limit.
SIGVTALRM: Use virtual signal. Computing is the process takes time CPU calls.
SIGPROF: including CPU time used by the process and the time of system calls.
SIGWINCH: window size is changed.
SIGIO: file descriptor is ready, indicating that you can input and output operations.
SIGPWR: power fail signal.
SIGSYS: Illegal system call.
