input_line()

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Прототип:

#include <stdio.h>
                                       
char * input_line( FILE *fp, 
                   char *buf, 
                   int bufsize );
                                       
extern int _input_line_max;

Аргументы:

fp

The file that you want to read from.

buf

A pointer to a buffer where the function can store the string that it reads.

bufsize

The size of the buffer, in bytes.

Библиотека:

libc

Описание:

The input_line() function gets a string of characters from the file designated by fp and stores them in the array pointed to by buf. The input_line() function stops reading characters when:

• end-of-file is reached
• a newline character is read
• bufsize - 1 characters have been read.

In addition, the input_line() function buffers the last _input_line_max lines internally. The _input_line_max variable is defined in <stdio.h>. You can set it before calling input_line() for the first time; its default value is 20. While the line is being read, the KEY_UP and KEY_DOWN keys can be used to move to the previous and next line respectively in a circular buffer of previously read lines. The newline character (\n) is replaced with the null character on input.

Возвращаемое значение:

≠NULL

A pointer to the input line.

NULL

Возникла ошибка или достигнут конец файла. Код ошибки записан в errno.

Примеры:

#include <stdlib.h>
#include <stdio.h>
                                       
#define SIZ 256
                                       
int _input_line_max;
                                       
int main( void )
{
    FILE    *fp;
    char    *p,
            buf[SIZ];
                                       
    fp              = stdin;    /* Or any stream */
    _input_line_max = 25;       /*  set before 1st call */
                                       
    while ( (p = input_line( fp, buf, SIZ )) != NULL )
    {
        printf( "%s\n", buf );
        fflush( stdout );
    }
        
    return (EXIT_SUCCESS);
}

Классификация:

ЗОСРВ «Нейтрино»

Точка остановки потока

Да

Обработчик прерываний

Нет

Обработчик сигналов

Нет

В потоке

Нет

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