Python 파일입출력 예제

import sys

print(1)
print('hello',' ','hello')


# sep 파라미터
x =0.2
s='hello'
print(str(x)+' ',s)
print(x,s,sep=' ')

# 기본적인 print()
print(sep=' ',end='\n')

# file 파라미터를 지정
print('hello world',file=sys.stdout)
print('error: hello wold',file=sys.stderr)

# file 출력
f=open('hello.txt','w')
print( type(f) )
print('hello world',file=f)
f.close()

# 참고
sys.stdout.write('Heloo wORld?~')

#textmode 가 default : t
f =open('test.txt','w',encoding='utf-8')
writesize  = f.write('안녕하세요\n 파이썬입니다')
f.close()

print(writesize)

# binary mode : b
f = open('test2.txt','wb')
writesize=f.write(bytes('안녕하세요\n 파이썬입니다',encoding='utf-8'))
f.close()
print(writesize)

# read test
f=open('test.txt','rt',encoding='utf-8')
text=f.read()
f.close()
print(text)

# binary read ": copy file
fsrc = open('1.jpg','rb')
data= fsrc.read()
fsrc.close()

print(type(fsrc))

fdest=open('2.jpg','wb')
fdest.write(data)
fdest.close()

f=open('test.txt','rt',encoding='utf-8')
text=f.read()
print(text)
f=open('test.txt','rt',encoding='utf-8')
text=f.read()
print('--------',text,'---------')


#
pos = f.tell()
print(pos)


# (offset, from_what)
#       ,0 (맨앞에서)
f.seek(16,0)
text=f.read()
print(text)


# f.seek(10,2)
# text=f.read()
# print(text)

# line 단위로 읽기
linenum=0
f2= open('fileio2.py','rt',encoding='utf-8')
while True :
    line = f2.readline()
    if line == '':
        f2.close()
        break
    linenum+=1
    print('{0}:{1}'.format(linenum,line),end='')


print('============================================')
f3 = open('fileio2.py','rt',encoding='utf-8')
lines=f3.readlines()
f3.close()

print(type(lines))
for linenum,line in enumerate(lines):
    print(linenum,':',line)

f=open('123.txt','wb')
f.write(b'0123456789')
f.close()

f=open('123.txt','rb')
print(f.tell())

f.seek(5,1)
data=f.read(2)
print(data)


f.seek(-5,1)
data=f.read(3)
print(data)


f.seek(0,2) # (맨끝 뒤로 이동)
data=f.read(2)
print(data)


# with ~ as

with open('fileio2.py','rt',encoding='utf-8') as f2 :
    for linenum,line in enumerate(f2.readlines()) :
        print('{0}:{1}'.format(linenum,line),end='')