very strange behavior in writing to file
I have very strange behavior.
For example,
with open("f","w") as fp:
fp.write(s) # s is string
If I write a lot of data then in the beginning of file I see garbage.
The same thing in the binary file.
If I change the mode from w or wb to a or ab then it's ok.
Do you have any idea ?
python python-3.x
asked Nov 23 '18 at 22:22
AlexAlex
22
add a comment |
I have very strange behavior.
For example,
with open("f","w") as fp:
fp.write(s) # s is string
If I write a lot of data then in the beginning of file I see garbage.
The same thing in the binary file.
If I change the mode from w or wb to a or ab then it's ok.
Do you have any idea ?
python python-3.x
asked Nov 23 '18 at 22:22
AlexAlex
22
add a comment |
I have very strange behavior.
For example,
with open("f","w") as fp:
fp.write(s) # s is string
If I write a lot of data then in the beginning of file I see garbage.
The same thing in the binary file.
If I change the mode from w or wb to a or ab then it's ok.
Do you have any idea ?
python python-3.x
asked Nov 23 '18 at 22:22
AlexAlex
22
I have very strange behavior.
For example,
with open("f","w") as fp:
fp.write(s) # s is string
If I write a lot of data then in the beginning of file I see garbage.
The same thing in the binary file.
If I change the mode from w or wb to a or ab then it's ok.
Do you have any idea ?
python python-3.x
python python-3.x
asked Nov 23 '18 at 22:22
AlexAlex
22
asked Nov 23 '18 at 22:22
AlexAlex
22
edited Nov 24 '18 at 9:48
Alex
asked Nov 23 '18 at 22:22
AlexAlex
22
asked Nov 23 '18 at 22:22
AlexAlex
22
asked Nov 23 '18 at 22:22
AlexAlex
22
22
add a comment |
add a comment |
1 Answer
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The w flag means "open for writing and truncate the file to zero length. The stream is positioned at the beginning of the file."; you'd probably want to open the file with the a flag which means "open the file for appending".
P.S. I can not write a comment because I do not have enough reputation.
answered Nov 23 '18 at 22:33
ElidorDDElidorDD
679
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
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active
oldest
votes
The w flag means "open for writing and truncate the file to zero length. The stream is positioned at the beginning of the file."; you'd probably want to open the file with the a flag which means "open the file for appending".
P.S. I can not write a comment because I do not have enough reputation.
answered Nov 23 '18 at 22:33
ElidorDDElidorDD
679
add a comment |
The w flag means "open for writing and truncate the file to zero length. The stream is positioned at the beginning of the file."; you'd probably want to open the file with the a flag which means "open the file for appending".
P.S. I can not write a comment because I do not have enough reputation.
answered Nov 23 '18 at 22:33
ElidorDDElidorDD
679
add a comment |
The w flag means "open for writing and truncate the file to zero length. The stream is positioned at the beginning of the file."; you'd probably want to open the file with the a flag which means "open the file for appending".
P.S. I can not write a comment because I do not have enough reputation.
answered Nov 23 '18 at 22:33
ElidorDDElidorDD
679
The w flag means "open for writing and truncate the file to zero length. The stream is positioned at the beginning of the file."; you'd probably want to open the file with the a flag which means "open the file for appending".
P.S. I can not write a comment because I do not have enough reputation.
answered Nov 23 '18 at 22:33
ElidorDDElidorDD
679
answered Nov 23 '18 at 22:33
ElidorDDElidorDD
679
answered Nov 23 '18 at 22:33
ElidorDDElidorDD
679
answered Nov 23 '18 at 22:33
ElidorDDElidorDD
679
679
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