Error can't open device: Too many open files

Question

After several hours of running the code, get the following error:

can't open device: Too many open files

Mi code is:

import signal
import os
from module.MFRC522 import MFRC522
from module.pinos import PinoControle
import RPi.GPIO as GPIO
import time
import sys
import Basedatos
import webcam
import correo
import subprocess
##import emergencia

import MySQLdb

#Impor tar modulos r e que r ido s
from time import strftime, localtime
import datetime
#from unidecode import unidecode

##from MFRC522 import MFRC522
##from pinos import PinoControle


class Nfc522(object):

    pc = PinoControle()
    MIFAREReader = None
    RST1 = 22 #GPIO
    RST2 = 22 #GPIO
    SPI_DEV0 = '/dev/spidev0.0'
    SPI_DEV1 = '/dev/spidev0.1'

    def obtem_nfc_rfid(self, autenticacao=False):
        try:
            self.MIFAREReader = MFRC522(self.RST1, self.SPI_DEV0)
##            while True:
            (status, TagType) = self.MIFAREReader.MFRC522_Request(self.MIFAREReader.PICC_REQIDL)
            (status, uid) = self.MIFAREReader.MFRC522_Anticoll()

            if status == self.MIFAREReader.MI_OK:
##                print "Ganesh 1"
                gid1 =  self.obtem_tag(self.MIFAREReader, status, uid, autenticacao)
##                    return gg
##                print "GID1:" + str(gg)
            else:
                self.pc.atualiza(self.RST1, self.pc.baixo())
##                print "GID1: No"

                gid1 = 0

        except Exception as e:
            print e

        try:    
            self.MIFAREReader = MFRC522(self.RST2, self.SPI_DEV1)


            #while True:
            (status, TagType) = self.MIFAREReader.MFRC522_Request(self.MIFAREReader.PICC_REQIDL)
            (status, uid) = self.MIFAREReader.MFRC522_Anticoll()

            if status == self.MIFAREReader.MI_OK:

                gid2= self.obtem_tag(self.MIFAREReader, status, uid, autenticacao)
##                print "GID2:" + str(ggg)
            else:
                self.pc.atualiza(self.RST2, self.pc.baixo())
##                print "GID2: No"
                gid2=0
##                    return None


        except Exception as e:
            print e
        #finally:
            #self.MIFAREReader.fecha_spi()

        return gid1,gid2

    def obtem_tag(self, MIFAREReader, status, uid, autenticacao):
        global TagID
        try:
            if autenticacao:
                # Chave padrão para a autenticação
                key = [0xFF,0xFF,0xFF,0xFF,0xFF,0xFF]
                MIFAREReader.MFRC522_SelectTag(uid)
                status = MIFAREReader.MFRC522_Auth(MIFAREReader.PICC_AUTHENT1A, 8, key, uid)
                if status == MIFAREReader.MI_OK:
                    MIFAREReader.MFRC522_Read(8)
                    MIFAREReader.MFRC522_StopCrypto1()
                else:
                    print "Erro na autenticação!"
                    return None
            tag_hexa = ''.join([str(hex(x)[2:4]).zfill(2) for x in uid[:-1][::-1]]) #Returns in hexadecimal
            return int(tag_hexa.upper(), 16) #Returns in decimal
        except Exception as e:
            print e

# Capture SIGINT for cleanup when the script is aborted
def end_read(signal,frame):
    global continue_reading
    print "trl+C captured, ending read."
    continue_reading = False
    GPIO.cleanup()

def ledencendido():
    GPIO.output(5, True)



def  inicializarGpio():
            GPIO.setwarnings(False)#Secolocanl a sadve rte nc i asen f a l s o

#
            GPIO.setmode(GPIO.BCM)#Mododet rabajoesGPIO.BOARD d i f e r e n t edebcm
            GPIO.setup(16,GPIO.OUT)#Colocae lpin11comos a l i d a
            GPIO.setup(17,GPIO.OUT)#Colocae lpin13comos a l i d a
            GPIO.setup(18,GPIO.OUT)#Colocae lpin15comos a l i d a
            GPIO.setup(19,GPIO.OUT)
            GPIO.setup(20,GPIO.OUT)
            GPIO.setup(24,GPIO.OUT)
            GPIO.setup(13,GPIO.OUT)
            GPIO.setup(27,GPIO.OUT)
            GPIO.setup(5,GPIO.OUT)


# Hook the SIGINT
signal.signal(signal.SIGINT, end_read)

nfc = Nfc522()

continue_reading = True
print "\nEsperando Tag\n---------------"
GPIO.cleanup()


while continue_reading:


    global TagID
    TagID=0
    print_opt = 0

    gid1,gid2 = nfc.obtem_nfc_rfid()
    inicializarGpio()

    ledencendido()
    doc = open('emergencia.txt', 'r+')# Abre el doc
    doc.seek(0,0)
    emer = doc.read(1)
    doc.close #cierra el doc
    if (emer == '1'):#Sil


        print('Estado de Emergencia')

    else:

        if gid1!=0:
            print "ID del primer Lector es:" + str(gid1)
            TagID=str(gid1)

            usuario= Basedatos.Validar_Acceso(TagID)
            print (usuario)
            if (usuario == None):#Siusuarioesnulo
                GPIO.output(13, True)
                GPIO.output(16, True)
                Basedatos.Insertar_Alerta(TagID)
                print('Acceso Denegado')#Indique
                time.sleep(1)
                GPIO.output(13, False)
                GPIO.output(16, False)
            else:
                print('Bienvenido')#Imprimabienvenido


                 GPIO.output(13, True)
                 GPIO.output(17, True)
                GPIO.output(24, True)
                time.sleep(3)
               GPIO.output(13, False)
               GPIO.output(17, False)
               GPIO.output(24, False)
               Basedatos.Insertar_Acceso(TagID)#Ing re s ee laccesoenl abase dedatos


            print_opt = 1


        if gid2!=0:
            print "ID del segundo Lector es:" + str(gid2)
            TagID=str(gid2)
            usuario2= Basedatos.Validar_Acceso(TagID)
            print (usuario2)

            if (usuario2 == None):#Siusuarioesnulo
                GPIO.output(13, True)
               GPIO.output(16, True)
                Basedatos.Insertar_Alerta(TagID)
                print('Acceso Denegado')#Indique

               time.sleep(1)
               GPIO.output(13, False)
               GPIO.output(16, False)

            else:


                print('Saliendo')
                GPIO.output(13, True)
               GPIO.output(17, True)
               GPIO.output(24, True)
                time.sleep(3)
               GPIO.output(13, False)
               GPIO.output(17, False)
                GPIO.output(24, False)

                Basedatos.Insertar_Acceso(TagID)#


            print_opt = 1

        if print_opt==1:
            print "\nEsperando Tag\n---------------\n"
            time.sleep(1)

Answer 1

You are not closing the emergencia.txt file and not checking if it is already open.

Change this line:

doc.close #cierra el doc

to this:

doc.close() #cierra el doc

You can read more about the close method here.

There are a couple of additional issues with your code:

• the indentation of your code is very inconsistent,
• you have insufficient error handling.