C語言函數大全(t開頭)

函數名: tell

功能: 取文件指針的當前位置

用法: long tell(int handle);

程序例:

#include
#include
#include
#include
int main(void)
{
int handle;
char msg[] = "Hello world";
if ((handle = open("TEST.$$$", O_CREAT | O_TEXT | O_APPEND)) == -1)
{
perror("Error:");
return 1;
}
write(handle, msg, strlen(msg));
printf("The file pointer is at byte %ld\n", tell(handle));
close(handle);
return 0;
}

函數名: textattr

功能: 設置文本屬性

用法: void textattr(int attribute);

程序例:

#include
int main(void)
{
int i;
clrscr();
for (i=0; i<9; i++)
{
textattr(i + ((i+1) << 4));
cprintf("This is a test\r\n");
}
return 0;
}

函數名: textbackground

功能: 選擇新的文本背景顏色

用法: void textbackground(int color);

程序例:

#include
int main(void)
{
int i, j;
clrscr();
for (i=0; i<9; i++)
{
for (j=0; j<80; j++)
cprintf("C");
cprintf("\r\n");
textcolor(i+1);
textbackground(i);
}
return 0;
}

函數名: textcolor

功能: 在文本模式中選擇新的字符顏色

用法: void textcolor(int color);

程序例:

#include
int main(void)
{
int i;
for (i=0; i<15; i++)
{
textcolor(i);
cprintf("Foreground Color\r\n");
}
return 0;
}

函數名: textheight

功能: 返回以像素為單位的字符串高度

用法: int far textheight(char far *textstring);

程序例:

#include
#include
#include
#include
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int y = 0;
int i;
char msg[80];
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, "");
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
}
/* draw some text on the screen */
for (i=1; i<11; i++)
{
/* select the text style, direction, and size */
settextstyle(TRIPLEX_FONT, HORIZ_DIR, i);
/* create a message string */
sprintf(msg, "Size: %d", i);
/* output the message */
outtextxy(1, y, msg);
/* advance to the next text line */
y += textheight(msg);
}
/* clean up */
getch();
closegraph();
return 0;
}

函數名: textmode

功能: 將屏幕設置成文本模式

用法: void textmode(int mode);

程序例:

#include
int main(void)
{
textmode(BW40);
cprintf("ABC");
getch();
textmode(C40);
cprintf("ABC");
getch();
textmode(BW80);
cprintf("ABC");
getch();
textmode(C80);
cprintf("ABC");
getch();
textmode(MONO);
cprintf("ABC");
getch();
return 0;
}

函數名: textwidth

功能: 返回以像素為單位的字符串寬度

用法: int far textwidth(char far *textstring);

程序例:

#include
#include
#include
#include
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int x = 0, y = 0;
int i;
char msg[80];
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, "");
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
}
y = getmaxy() / 2;
settextjustify(LEFT_TEXT, CENTER_TEXT);
for (i=1; i<11; i++)
{
/* select the text style, direction, and size */
settextstyle(TRIPLEX_FONT, HORIZ_DIR, i);
/* create a message string */
sprintf(msg, "Size: %d", i);
/* output the message */
outtextxy(x, y, msg);
/* advance to the end of the text */
x += textwidth(msg);
}
/* clean up */
getch();
closegraph();
return 0;
}

函數名: time

功能: 取一天的時間

用法: logn time(long *tloc);

程序例:

#include
#include
#include
int main(void)
{
time_t t;
t = time(NULL);
printf("The number of seconds since January 1, 1970 is %ld",t);
return 0;
}

函數名: tmpfile

功能: 以二進制方式打開暫存文件

用法: FILE *tmpfile(void);

程序例:

#include
#include
int main(void)
{
FILE *tempfp;
tempfp = tmpfile();
if (tempfp)
printf("Temporary file created\n");
else
{
printf("Unable to create temporary file\n");
exit(1);
}
return 0;
}


函數名: tmpnam

功能: 創建一個唯一的文件名

用法: char *tmpnam(char *sptr);

程序例:

#include
int main(void)
{
char name[13];
tmpnam(name);
printf("Temporary name: %s\n", name);
return 0;
}

函數名: tolower

功能: 把字符轉換成小寫字母

用法: int tolower(int c);

程序例:

#include
#include
#include
int main(void)
{
int length, i;
char *string = "THIS IS A STRING";
length = strlen(string);
for (i=0; i {
string[i] = tolower(string[i]);
}
printf("%s\n",string);
return 0;
}

函數名: toupper

功能: 把字符轉換成大寫字母

用法: int toupper(int c);

程序例:

#include
#include
#include
int main(void)
{
int length, i;
char *string = "this is a string";
length = strlen(string);
for (i=0; i {
string[i] = toupper(string[i]);
}
printf("%s\n",string);
return 0;
}

函數名: tzset

功能: UNIX時間兼容函數

用法: void tzset(void);

程序例:

#include
#include
#include
int main(void)
{
time_t td;
putenv("TZ=PST8PDT");
tzset();
time(&td);
printf("Current time = %s\n", asctime(localtime(&td)));
return 0;
}