# sigset_t - overview of system data types - man(3type) - [phpMan] [_system_data_types_(7)](https://www.chedong.com/phpMan.php/man/systemdatatypes/7/markdown) Miscellaneous Information Manual [_system_data_types_(7)](https://www.chedong.com/phpMan.php/man/systemdatatypes/7/markdown) ## NAME system_data_types - overview of system data types ## DESCRIPTION _siginfo_t_ _Include_: __. Alternatively, __. typedef struct { int si_signo; /* Signal number */ int si_code; /* Signal code */ pid_t si_pid; /* Sending process ID */ uid_t si_uid; /* Real user ID of sending process */ void *si_addr; /* Memory location which caused fault */ int si_status; /* Exit value or signal */ union sigval si_value; /* Signal value */ } siginfo_t; Information associated with a signal. For further details on this structure (includ‐ ing additional, Linux-specific fields), see [**sigaction**(2)](https://www.chedong.com/phpMan.php/man/sigaction/2/markdown). _Conforming_ _to_: POSIX.1-2001 and later. _See_ _also_: [**pidfd_send_signal**(2)](https://www.chedong.com/phpMan.php/man/pidfdsendsignal/2/markdown), [**rt_sigqueueinfo**(2)](https://www.chedong.com/phpMan.php/man/rtsigqueueinfo/2/markdown), [**sigaction**(2)](https://www.chedong.com/phpMan.php/man/sigaction/2/markdown), [**sigwaitinfo**(2)](https://www.chedong.com/phpMan.php/man/sigwaitinfo/2/markdown), [**psiginfo**(3)](https://www.chedong.com/phpMan.php/man/psiginfo/3/markdown) _sigset_t_ _Include_: __. Alternatively, __, or __. This is a type that represents a set of signals. According to POSIX, this shall be an integer or structure type. _Conforming_ _to_: POSIX.1-2001 and later. _See_ _also_: [**epoll_pwait**(2)](https://www.chedong.com/phpMan.php/man/epollpwait/2/markdown), [**ppoll**(2)](https://www.chedong.com/phpMan.php/man/ppoll/2/markdown), [**pselect**(2)](https://www.chedong.com/phpMan.php/man/pselect/2/markdown), [**sigaction**(2)](https://www.chedong.com/phpMan.php/man/sigaction/2/markdown), [**signalfd**(2)](https://www.chedong.com/phpMan.php/man/signalfd/2/markdown), **sigpend‐** [**ing**(2)](https://www.chedong.com/phpMan.php/man/ing/2/markdown), [**sigprocmask**(2)](https://www.chedong.com/phpMan.php/man/sigprocmask/2/markdown), [**sigsuspend**(2)](https://www.chedong.com/phpMan.php/man/sigsuspend/2/markdown), [**sigwaitinfo**(2)](https://www.chedong.com/phpMan.php/man/sigwaitinfo/2/markdown), [**signal**(7)](https://www.chedong.com/phpMan.php/man/signal/7/markdown) ## NOTES The structures described in this manual page shall contain, at least, the members shown in their definition, in no particular order. Most of the integer types described in this page don't have a corresponding length modifier for the [**printf**(3)](https://www.chedong.com/phpMan.php/man/printf/3/markdown) and the [**scanf**(3)](https://www.chedong.com/phpMan.php/man/scanf/3/markdown) families of functions. To print a value of an integer type that doesn't have a length modifier, it should be converted to _intmax_t_ or _uintmax_t_ by an explicit cast. To scan into a variable of an integer type that doesn't have a length mod‐ ifier, an intermediate temporary variable of type _intmax_t_ or _uintmax_t_ should be used. When copying from the temporary variable to the destination variable, the value could overflow. If the type has upper and lower limits, the user should check that the value is within those limits, before actually copying the value. The example below shows how these conversions should be done. ### Conventions used in this page In "Conforming to" we only concern ourselves with C99 and later and POSIX.1-2001 and later. Some types may be specified in earlier versions of one of these standards, but in the inter‐ ests of simplicity we omit details from earlier standards. In "Include", we first note the "primary" header(s) that define the type according to either the C or POSIX.1 standards. Under "Alternatively", we note additional headers that the stan‐ dards specify shall define the type. ## EXAMPLES The program shown below scans from a string and prints a value stored in a variable of an in‐ teger type that doesn't have a length modifier. The appropriate conversions from and to _int‐_ _max_t_, and the appropriate range checks, are used as explained in the notes section above. #include #include #include #include int main (void) { static const char *const str = "500000 us in half a second"; suseconds_t us; intmax_t tmp; /* Scan the number from the string into the temporary variable. */ sscanf(str, "%jd", &tmp); /* Check that the value is within the valid range of suseconds_t. */ if (tmp < -1 || tmp > 1000000) { fprintf(stderr, "Scanned value outside valid range!\n"); exit(EXIT_FAILURE); } /* Copy the value to the suseconds_t variable 'us'. */ us = tmp; /* Even though suseconds_t can hold the value -1, this isn't a sensible number of microseconds. */ if (us < 0) { fprintf(stderr, "Scanned value shouldn't be negative!\n"); exit(EXIT_FAILURE); } /* Print the value. */ printf("There are %jd microseconds in half a second.\n", (intmax_t) us); exit(EXIT_SUCCESS); } ## SEE ALSO [**feature_test_macros**(7)](https://www.chedong.com/phpMan.php/man/featuretestmacros/7/markdown), [**standards**(7)](https://www.chedong.com/phpMan.php/man/standards/7/markdown) Linux man-pages 6.7 2023-10-31 [_system_data_types_(7)](https://www.chedong.com/phpMan.php/man/systemdatatypes/7/markdown)