cfsetispeed()

Set the input baud rate in a termios structure

Synopsis:

#include <termios.h>

int cfsetispeed( struct termios* termios_p,
                 speed_t speed );

Library:

libc

Description:

The cfsetispeed() function sets the input baud rate within the termios structure pointed to by termios_p to be speed. Valid values for speed are defined in <termios.h>.

A valid termios control structure for an opened device can be obtained using the tcgetattr() function.

The new baud rate isn't effective until tcsetattr() is called with this modified termios structure. Attempts to set baud rates to values not supported by the hardware are ignored, and cause tcsetattr() to return an error, but cfsetispeed() doesn't indicate an error. Attempts to set input baud rates to a value that's different from the output baud rate, when the hardware doesn't support split baud rates, cause the input baud rate to be ignored, but no error is generated.

Returns:

0

Success.

-1

An error occurred (errno is set).

Errors:

EINVAL

One of the arguments is invalid.

ENOTTY

This function isn't supported by the system.

Examples:

#include <termios.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>

int main( void )
  {
    int fd;
    struct termios termios_p;
    speed_t speed;

    fd = open( "/dev/ser1", O_RDWR );
    tcgetattr( fd, &termios_p);

    /*
     *    Set input baud rate
     */
    speed = 9600;
    cfsetispeed( &termios_p, speed );
    tcsetattr( fd, TCSADRAIN, &termios_p);

    close( fd );
    return EXIT_SUCCESS;
  }

Classification:

POSIX 1003.1

See also:

errno, cfgetispeed(), cfgetospeed(), cfsetospeed(), tcgetattr(), tcsetattr()