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25 .TH BSD_SIGNAL 3 2013-10-22 "" "Linux Programmer's Manual"
27 bsd_signal \- signal handling with BSD semantics
29 .BR "#define _XOPEN_SOURCE" " /* See feature_test_macros(7) */"
31 .B #include <signal.h>
33 .B typedef void (*sighandler_t)(int);
35 .BI "sighandler_t bsd_signal(int " signum ", sighandler_t " handler );
39 function takes the same arguments, and performs the same task, as
42 The difference between the two is that
44 is guaranteed to provide reliable signal semantics, that is:
45 a) the disposition of the signal is not reset to the default
46 when the handler is invoked;
47 b) delivery of further instances of the signal is blocked while
48 the signal handler is executing; and
49 c) if the handler interrupts a blocking system call,
50 then the system call is automatically restarted.
51 A portable application cannot rely on
53 to provide these guarantees.
57 function returns the previous value of the signal handler, or
64 .SS Multithreading (see pthreads(7))
67 function is thread-safe.
70 POSIX.1-2008 removes the specification of
72 recommending the use of
78 should be avoided; use
82 On modern Linux systems,
89 provided unreliable signal semantics; see
96 this type is defined only if the
98 feature test macro is defined.