raise. McGraw-Hill The Complete Reference Fourth Edition

C h a p t e r 3 0 : U t i l i t y F u n c t i o n s

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The qsort( ) function sorts the array pointed to by buf using a Quicksort (developed by C.A.R. Hoare). The Quicksort is the best general-purpose sorting algorithm. Upon termination, the array will be sorted. The number of elements in the array is specified by num, and the size (in bytes) of each element is described by size.

The function pointed to by compare is used to compare an element of the array with the key. The form of the compare function must be as follows: int func_name(const void *arg1, const void *arg2);

It must return values as described here:

Comparison

arg1 is less than arg2

arg1 is equal to arg2

arg1 is greater than arg2

Value Returned

Less than zero

Zero

Greater than zero

The array is sorted into ascending order with the lowest address containing the lowest element.

A related function is bsearch( ).

raise

#include <csignal> int raise(int signal);

The raise( ) function sends the signal specified by signal to the executing program.

It returns zero if successful, and nonzero otherwise. It uses the header <csignal>.

The following signals are defined by Standard C++. Of course, your compiler is free to provide additional signals.

Macro

SIGABRT

SIGFPE

SIGILL

Meaning

Termination error

Floating-point error

Bad instruction