Circuit:-


Holding the DHT11 towards you (the one with grid), the left pin is connected to VCC (pin 1).The data pin is next  after VCC and is connected to
(pin 7).Next pin is NC(no connection).Finally the last pin is connected to GND(pin 25).

pi-dh11

Software:-

WiringPi which uses C like Arduino language is used to read the sensor value. WiringPi is maintained under GIT for ease of change tracking.If you do not have GIT installed, then under any of the Debian releases, you can install it with-

sudo apt-get install git-core

To obtain WiringPi using GIT:

git clone git://git.drogon.net/wiringPi

If you have already used the clone operation for the first time, then

cd wiringPi

git pull origin

Will fetch an updated version then you can re-run the build script below.

To build/install there is a new simplified script:

cd wiringPi

Create and Open temp_rh_sensor.c file.

 
sudo nano temp_rh_sensor.c

Open the below link and copy the code to temp_rh_sensor.c file and press Ctrl + X key,then press Y to save file.


https://osoyoo.com/driver/temp_rh_sensor.c

Also You can input below command to download the temp_rh_sensor.c file directly.

sudo wget http://osoyoo.com/driver/temp_rh_sensor.c 

Compile the code as…

gcc -o sensor temp_rh_sensor.c -L/usr/local/lib -lwiringPi

Now execute it…
sudo ./sensor

[ Humidity = 87.0 % Temperature = 32.2 *C (90.0 *F) ]