printf("First address: %Fp\n", fptr);
fptr = farrealloc(fptr,20);
printf("New address : %Fp\n", fptr);
farfree(fptr);
return 0;
}
函数名: fclose
功 能: 关闭一个流
用 法: int fclose(FILE *stream);
程序例:
#include
#include
int main(void)
{
FILE *fp;
char buf[11] = "0123456789";
/* create a file containing 10 bytes */
fp = fopen("DUMMY.FIL", "w");
fwrite(&buf, strlen(buf), 1, fp);
/* close the file */
fclose(fp);
return 0;
}
函数名: fcloseall
功 能: 关闭打开流
用 法: int fcloseall(void);
程序例:
#include
int main(void)
{
int streams_closed;
/* open two streams */
fopen("DUMMY.ONE", "w");
fopen("DUMMY.TWO", "w");
/* close the open streams */
streams_closed = fcloseall();
if (streams_closed == EOF)
/* issue an error message */
perror("Error");
else
/* print result of fcloseall() function */
printf("%d streams were closed.\n", streams_closed);
return 0;
}
函数名: fcvt
功 能: 把一个浮点数转换为字符串
用 法: char *fcvt(double value, int ndigit, int *decpt, int *sign);
程序例:
#include
#include
#include
int main(void)
{
char *string;
double value;
int dec, sign;
int ndig = 10;
clrscr();
value = 9.876;
string = ecvt(value, ndig, &dec, &sign);
printf("string = %s dec = %d \
sign = %d\n", string, dec, sign);
value = -123.45;
ndig= 15;
string = ecvt(value,ndig,&dec,&sign);
printf("string = %s dec = %d sign = %d\n",
string, dec, sign);
value = 0.6789e5; /* scientific
notation */
ndig = 5;
string = ecvt(value,ndig,&dec,&sign);
printf("string = %s dec = %d\
sign = %d\n", string, dec, sign);
return 0;
}
函数名: fdopen
功 能: 把流与一个文件句柄相接
用 法: FILE *fdopen(int handle, char *type);
程序例:
#include
#include
#include
#include
int main(void)
{
int handle;
FILE *stream;
/* open a file */
handle = open("DUMMY.FIL", O_CREAT,
S_IREAD | S_IWRITE);
/* now turn the handle into a stream */
stream = fdopen(handle, "w");
if (stream == NULL)
printf("fdopen failed\n");
else
{
fprintf(stream, "Hello world\n");
fclose(stream);
}
return 0;
}
函数名: feof
功 能: 检测流上的文件结束符
用 法: int feof(FILE *stream);
程序例:
#include
int main(void)
{
FILE *stream;
/* open a file for reading */
stream = fopen("DUMMY.FIL", "r");
/* read a character from the file */
fgetc(stream);
/* check for EOF */
if (feof(stream))
printf("We have reached end-of-file\n");
/* close the file */
fclose(stream);
return 0;
}
函数名: ferror
功 能: 检测流上的错误
用 法: int ferror(FILE *stream);
程序例:
#include
int main(void)
{
FILE *stream;
/* open a file for writing */
stream = fopen("DUMMY.FIL", "w");
/* force an error condition by attempting to read */
(void) getc(stream);
if (ferror(stream)) /* test for an error on the stream */
{
/* display an error message */
printf("Error reading from D