How to make QFile read the whole line
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its a single line data i have taken sreenshot like this . After the data 61 the next starts as d2.
As per the above image the file read reads till A.,?E>t 1?dWQA.,D E_??n1?d7be1526df618c0c4d1bab3959adb65ada9f20bd969493e532a7861d29bc6e698
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@ManiRon
in that image b5afa24a9fa264a178f5ae63c7eff6cf this is my checksum after that a Nul character is there after which my actual data starts@ManiRon
OK, in that case it sounds right if it is followed by a "Nul". Personally I would put a comment into your code then to explain that is why you are seeking to byte #33.I don't see anything which would stop at a NUL in your code. What makes you think it is doing so? Are you just relying on the output of
qDebug("FILEDATA %s",fileData.data());and thinking that shows it has not read past a NUL, that may be an artefact of howqDebug()displays the data? Try debugging out the length of the data? -
@ManiRon
OK, in that case it sounds right if it is followed by a "Nul". Personally I would put a comment into your code then to explain that is why you are seeking to byte #33.I don't see anything which would stop at a NUL in your code. What makes you think it is doing so? Are you just relying on the output of
qDebug("FILEDATA %s",fileData.data());and thinking that shows it has not read past a NUL, that may be an artefact of howqDebug()displays the data? Try debugging out the length of the data?@JonB Actually my requirement is to calculate checksum for the data and store it in the same file where the data i am writing to . So i planned to write the checksum at the begining and followed by the data.
Now when i start the application i will validate the file by reading the checksum stored in file and compare it with the remaining data in file by calculating checksum for them .
Note the stored checksum is calculated using the data and not the whole file
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could you replace
fileData = file.read(size_of_file);with :fileData.resize(size_of_file); const auto actualRead = file.read(fileData.data(),size_of_file); Q_ASSERT(actualRead==size_of_file);"La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
~Napoleon BonaparteOn a crusade to banish setIndexWidget() from the holy land of Qt
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could you replace
fileData = file.read(size_of_file);with :fileData.resize(size_of_file); const auto actualRead = file.read(fileData.data(),size_of_file); Q_ASSERT(actualRead==size_of_file); -
@VRonin said in How to make QFile read the whole line:
actualRead
I tried sir but i am getting this kind of error
@ManiRon It's not hard to fix:
const qint64 actualRead = file.read(fileData.data(),size_of_file); -
@ManiRon It's not hard to fix:
const qint64 actualRead = file.read(fileData.data(),size_of_file); -
could you replace
fileData = file.read(size_of_file);with :fileData.resize(size_of_file); const auto actualRead = file.read(fileData.data(),size_of_file); Q_ASSERT(actualRead==size_of_file); -
@ManiRon
OK, in that case it sounds right if it is followed by a "Nul". Personally I would put a comment into your code then to explain that is why you are seeking to byte #33.I don't see anything which would stop at a NUL in your code. What makes you think it is doing so? Are you just relying on the output of
qDebug("FILEDATA %s",fileData.data());and thinking that shows it has not read past a NUL, that may be an artefact of howqDebug()displays the data? Try debugging out the length of the data?No sir i checked the read by removing the NUL from the data in the file and i was able to see that it read the whole data and qDebug() was displaying the full data
This is the whole data when i removed the NUL : " WQA.,?E>t 1?dWQA.,D E_??n1?d7be1526df618c0c4d1bab3959adb65ada9f20bd969493e532a7861d29bc6e698{TB.)? V1??n1?dS[H21?z7_??n1?d340819615bcd7cb87459cac37070456eb0af53716c1f0064c4771857728d3777 "
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No sir i checked the read by removing the NUL from the data in the file and i was able to see that it read the whole data and qDebug() was displaying the full data
This is the whole data when i removed the NUL : " WQA.,?E>t 1?dWQA.,D E_??n1?d7be1526df618c0c4d1bab3959adb65ada9f20bd969493e532a7861d29bc6e698{TB.)? V1??n1?dS[H21?z7_??n1?d340819615bcd7cb87459cac37070456eb0af53716c1f0064c4771857728d3777 "
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@ManiRon said in How to make QFile read the whole line:
but thsi doest read the full data
What is the output of
qDebug() << actualRead << size_of_file;?
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@ManiRon said in How to make QFile read the whole line:
but thsi doest read the full data
What is the output of
qDebug() << actualRead << size_of_file;?
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@jsulm said in How to make QFile read the whole line:
size_of_file
Size = 194 .
I thought it was qdebug problem so i wrote the data read from the file to another file then also it remains the same as the data shown in the debug
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@ManiRon
"What can we do" about what? You've spent the whole time claiming the read stops at the NUL, now you confirm it does not, so what's the problem? -
@ManiRon
"What can we do" about what? You've spent the whole time claiming the read stops at the NUL, now you confirm it does not, so what's the problem?
