chap11.lst

Borland C++ Builder The Complete Reference 例程源代码

  } 
 
  while((ch=getc(fp))!=EOF) 
    printf("%c", ch); 
 
  fclose(fp); 
 
  return 0; 
}

listing 36
do { 
  printf("1: Check spelling\n"); 
  printf("2: Correct spelling\n"); 
  printf("3: Look up a word in the dictionary\n"); 
  printf("4: Quit\n"); 
 
  printf("\nEnter your selection: "); 
  choice = getch(); 
} while(!strchr("1234", choice));

listing 37
#include <stdio.h> 
 
int main(void) 
{ 
  char s[256], *p; 
 
  p = s; 
 
  while((*p++=getchar())!='\n') ; 
  *p = '\0';  /* add null terminator */ 
  printf(s); 
 
  return 0; 
}

listing 38
#include <stdio.h> 
#include <stdlib.h> 
 
int main(void) 
{ 
  FILE *fp; 
  char fname[128]; 
 
  printf("Enter filename: "); 
  gets(fname); 
 
  if((fp=fopen(fname, "r"))==NULL) { 
    printf("Cannot open file.\n"); 
    exit(1); 
  } 
 
/* ...*/ 
 
  fclose(fp); 
  return 0; 
}

listing 39
#include <stdio.h> 
#include <stdlib.h> 
 
int main(void) 
{ 
  FILE *fp; 
  int sum = 0; 
 
  if((fp=fopen("inttest", "rb"))==NULL) { 
    printf("Cannot open file.\n"); 
    exit(1); 
  } 
 
  while(!feof(fp)) 
    sum = getw(fp)+sum; 
 
  printf("The sum is %d", sum); 
  fclose(fp); 
 
  return 0; 
}

listing 40
if(isatty(fd)) printf("is a character device"); 
else printf("is not a character device");

listing 41
lock(fd, 0, 128);

listing 42
if(locking(fd, LK_UNLOCK, 10)) { 
  // process error 
}

listing 43
#include <stdio.h> 
#include <fcntl.h> 
#include <sys\stat.h> 
#include <io.h> 
#include <stdlib.h> 
 
#define BUF_SIZE  128 
 
/* read buffers using lseek() */ 
int main(int argc, char *argv[]) 
{ 
  char buf[BUF_SIZE+1], s[10]; 
  int fd, sector; 
 
  buf[BUF_SIZE+1] = '\0'; /* null terminate buffer for printf */ 
  if((fd=open(argv[1], O_RDONLY | O_BINARY))==-1) { /* open for write */ 
    printf("Cannot open file.\n"); 
    exit(0); 
  } 
  do { 
    printf("Buffer: "); 
    gets(s); 
 
    sector = atoi(s); /* get the sector to read */ 
 
    if(lseek(fd, (long)sector*BUF_SIZE,0)==-1L) 
      printf("Seek Error\n"); 
 
    if(read(fd, buf, BUF_SIZE)==0) { 
      printf("Read Error\n"); 
    } 
    else { 
      printf("%s\n", buf); 
    } 
  } while(sector > 0); 
  close(fd); 
 
  return 0; 
}

listing 44
if((fd=open(filename, mode)) == -1)  { 
  printf("Cannot open file.\n"); 
  exit(1); 
}

listing 45
#include <stdio.h> 
#include <math.h> 
#include <errno.h> /* contains declaration for errno */ 
 
int main(void) 
{ 
  /* this will generate a domain error */ 
  asin(10.0); 
  if(errno==EDOM) 
    perror("Program Error Test"); 
 
  return 0; 
}

listing 46
printf("Hi %c %d %s", 'c', 10, "there!");

listing 47
int i; 
 
printf("this is a test %n", &i); 
printf("%d", i);

listing 48
#include <stdio.h> 
 
int main(void) 
{ 
  /* This prints "this is a test" left-justified 
     in a 20-character field. 
  */ 
  printf("%-20s", "this is a test"); 
 
  /* This prints a float with 3 decimal places in a 
     10-character field. The output will be "    12.235". 
  */ 
  printf("%10.3f", 12.234657); 
  return 0; 
}

listing 49
for(; *str; str++) putc(*str, fp);

listing 50
putch('X');

listing 51
for(; *str; str++) putchar(*str);

listing 52
#include <stdio.h> 
#include <string.h> 
 
int main(void) 
{ 
  char str[80]; 
 
  strcpy(str, "this is an example"); 
  puts(str); 
 
  return 0; 
}

listing 53
putw(100, fp);

listing 54
#include <stdio.h> 
#include <io.h> 
#include <fcntl.h> 
#include <stdlib.h> 
 
int main(void) 
{ 
  int fd; 
  char buffer[100]; 
 
  if((fd=open("TEST.TST", O_RDONLY))==-1) { 
    printf("Cannot open file.\n"); 
    exit(1); 
  } 
 
  if(read(fd, buffer, 100)!=100) 
    printf("Possible read error.\n"); 
 
  return 0; 
}

listing 55
#include <stdio.h> 
 
int main(int argc, char *argv[]) 
{ 
  if(remove(argv[1])==-1) 
    printf("Remove Error\n"); 
 
  return 0; 
}

listing 56
#include <stdio.h> 
 
int main(int argc, char *argv[]) 
{ 
  if(rename(argv[1], argv[2])!=0) 
    printf("Rename Error\n"); 
 
  return 0; 
}

listing 57
void re_read(FILE *fp) 
{ 
  /* read once */ 
  while(!feof(fp)) putchar(getc(fp)); 
 
  rewind(fp); 
 
  /* read twice */ 
  while(!feof(fp)) putchar(getc(fp)); 
}

listing 58
scanf("%d", &count);

listing 59
scanf("%s", address);

listing 60
scanf("%d%d", &r, &c);

listing 61
scanf("%d%*c%d", &x, &y);

listing 62
scanf("%20s", address);

listing 63
scanf("%c%c%c", &a, &b, &c);

listing 64
scanf("%st%s", &x, &y);

listing 65
%[ABC]

listing 66
%[A-Z]

listing 67
char str[80]; 
int i; 
 
/* read a string and an integer */ 
scanf("%s%d", str, &i); 
 
/* read up to 79 chars into str */ 
scanf("%79s", str); 
 
/* skip the integer between the two strings */ 
scanf("%s%*d%s", str, &i, str);

listing 68
char buffer[BUFSIZ]; 
/* ... */ 
setbuf(fp,buffer);

listing 69
setmode(fd, O_TEXT)

listing 70
#include <stdio.h> 
char buffer[128]; 
/* ... */ 
setvbuf(fp, buffer, _IOLBF, 128);

listing 71
if((fd=sopen(filename, access, shflag, mode)) ==-1)  { 
  printf("Cannot open file.\n"); 
  exit(1); 
}

listing 72
char str[80]; 
sprintf(str, "%s %d %c", "one", 2, '3');

listing 73
#include <stdio.h> 
 
int main(void) 
{ 
  char str[80]; 
  int i; 
 
  sscanf("hello 1 2 3 4 5", "%s%d", str, &i); 
  printf("%s %d", str, i); 
 
  return 0; 
}

listing 74
#include <stdio.h> 
#include <sys\stat.h> 
#include <stdlib.h> 
 
int main(void) 
{ 
  FILE *fp; 
  struct stat buff; 
 
  if((fp=fopen("test", "rb"))==NULL) { 
    printf("Cannot open file.\n"); 
    exit(1); 
  } 
 
  /* fill the stat structure */ 
  stat("test", &buff); 
 
  printf("Size of the file is: %ld\n", buff.st_size); 
  fclose(fp); 
 
  return 0; 
}

listing 75
long pos; 
/* ... */ 
pos = tell(fd); 
printf("Position indicator is %ld bytes from the start", pos);

listing 76
FILE *temp; 
 
if(!(temp=tmpfile())) { 
  printf("Cannot open temporary work file.\n"); 
  exit(1); 
}

listing 77
#include <stdio.h> 
 
int main(void) 
{ 
  char name[40]; 
  int i; 
  for(i=0; i<3; i++) { 
    tmpnam(name); 
    printf("%s ", name); 
  } 
 
  return 0; 
}

listing 78
void read_word(FILE *fp, char *token) 
{ 
 
  while(isalpha(*token=getc(fp))) token++; 
 
  ungetc(fp, *token); 
}

listing 79
#include <stdio.h> 
#include <conio.h> 
 
int main(void) 
{ 
  char ch; 
 
  ch = getch(); // get keypress 
  putch(ch); // show the key 
  ungetch(ch);  // return to buffer 
  ch = getch(); // get same key again 
  putch(ch); // show the key again 
 
  return 0; 
}

listing 80
#include <stdio.h> 
#include <dos.h> 
 
int main(int argc, char *argv[]) 
{ 
  if(unlink(argv[1])==-1) 
    printf("Cannot remove file."); 
 
  return 0; 
}

listing 81
unlock(fd, 0, 128);

listing 82
#include <stdio.h> 
#include <stdarg.h> 
 
void print_message(char *, ...); 
 
int main(void) 
{ 
  print_message("Cannot open file %s","test"); 
 
  return 0; 
} 
 
void print_message( char *format, ...) 
{ 
  va_list ptr; /* get an arg ptr */ 
 
  /* initialize ptr to point to the first argument after the 
     format string 
  */ 
  va_start(ptr, format); 
  /* print out message */ 
  vprintf(format, ptr); 
  va_end(ptr); 
}

listing 83
#include <stdio.h> 
#include <stdarg.h> 
 
void read_int(int num, ...); 
 
int main(void) 
{ 
  int a, b; 
  read_int(2, &a, &b); 
  printf("%d %d", a, b); 
 
  return 0; 
} 
 
void read_int(int num, ...) 
{ 
  va_list ptr; /* get an arg ptr */ 
 
  /* initialize ptr to point to the first argument after the 
     format string 
  */ 
  va_start(ptr, num); 
 
  printf("Enter %d integers: ", num); 
  /* read ints */ 
  vscanf("%d %d", ptr); 
 
  va_end(ptr); 
}

listing 84
#include <stdio.h> 
#include <io.h> 
#include <fcntl.h> 
#include <stdlib.h> 
 
int main(void) 
{ 
  int fd; 
  char buffer[100]; 
 
  if((fd=open("test", O_WRONLY))==-1) { 
    printf("Cannot open file.\n"); 
    exit(1); 
  } 
 
  gets(buffer); 
 
  if(write(fd, buffer, 100)!=100) 
    printf("Write Error"); 
  close(fd); 
 
  return 0; 
}