C language Function Encyclopedia (beginning of G)

Function Name: GCVT

Function: Converts floating-point numbers to strings

Usage: Char *gcvt (double value, int ndigit, char *buf);

program Example:

#include
#include
int main(void)
{
char str[25];
double num;
int sig = 5; /* significant digits */
/* a regular number */
num = 9.876;
gcvt(num, sig, str);
printf("string = %s\n", str);
/* a negative number */
num = -123.4567;
gcvt(num, sig, str);
printf("string = %s\n", str);
/* scientific notation */
num = 0.678e5;
gcvt(num, sig, str);
printf("string = %s\n", str);
return(0);
}

Function Name: Geninterrupt

Function: Produces a soft interrupt

Usage: void geninterrupt (int intr_num);

program Example:

#include
#include
/* function prototype */
void writechar(char ch);
int main(void)
{
clrscr();
gotoxy(80,25);
writechar('*');
getch();
return 0;
}
/*
outputs a character at the current cursor
position using the video BIOS to avoid the
scrolling of the screen when writing to
location (80,25).
*/
void writechar(char ch)
{
struct text_info ti;
/* grab current text settings */
gettextinfo(&ti);
/* interrupt 0x10 sub-function 9 */
_AH = 9;
/* character to be output */
_AL = ch;
_BH = 0; /* video page */
_BL = ti.attribute; /* video attribute */
_CX = 1; /* repetition factor */
geninterrupt(0x10); /* output the char */
}