signalfd: Pass signals along a file.

Functions
int	signalfd_init (void)
void	signalfd_catch (int sig)
void	signalfd_uncatch (int sig)
void	signalfd_close (void)

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Function Documentation

void signalfd_catch

(

int

sig

)

Mark a signal as being caught through the signalfd interface.

void signalfd_close

(

void

)

Close the signalfd interface.

int signalfd_init

(

void

)

Initialize the signal file descriptor.

This function creates a pipe through which signals will get passed. This is a way of handling signals that avoids most problems posed by UNIX signals. When a signal is caught by this interface, the numerical value of the signal is passed down the pipe as a native integer. The file descriptor is set to non-blocking mode to prevent blocking when reading from it.

To use the file descriptor, use either poll or select to determine when it is readable. When it becomes readable, read a single byte from it. The value of this byte indicates what signal was caught.

Due to the global nature of UNIX signal handling, only a single signalfd interface may be active at any time. Do not call signalfd_init multiple times without calling signalfd_close first.

Returns:

-1 if an error occurred, otherwise the return value is the file descriptor opened for reading.

void signalfd_uncatch

(

int

sig

)

Unmark a signal as being caught through the signalfd interface.

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