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Questions tagged [null-character]

The null character, abbreviated NUL, is a control character with the value zero.

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in linux, is it normal that there is no null character at the end of file

in linux, is it normal that there is no null character at the end of file? I made a empty file and open with mouse pad write az. save it. when I open the file up with hex editor, there is no null character but 0a is there. what null character should…
kim taeyun
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ASCII value = 0 and '\0'

I have read this post. But when I tried: printf("before null %c after null\n", 0); // (ASCII=0) != '\0' ?? instead of getting: before null I got: before null after null So my question is: Is ASCII value 0 actually equal to '\0'?
iamsuperwen
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Using scanf for character input, but the do-while loop wont stop at the null character

I'm completely new to programming (1st term in uni) and I can't keep up with my lecturer. At the moment I'm stuck on this exercise (for much more time than I'm willing to admit). I've tried to find help on the internet (in this site and others as…
S. Kats.
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How to make grep separate output by NULL characters?

Suppose we are doing a multiline regex pattern search on a bunch of files and we want to extract the matches from grep. By default, grep outputs matches separated by newlines, but since we are doing multiline patterns this creates the inconvenience…
chtenb
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How can I match a null byte (0x00) in the Visual Studio binary editor with a find using a regular expression?

Open a file in the Visual Studio binary editor that contains a null byte (0x00), then use the Quick Find feature (Ctrl +F) to find null bytes. I would have thought I could use a regular expression such as \x00 to match null bytes but it doesn't…
Paul Killick
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How to create C++ istringstream from a char array with null(0) characters?

I have a char array which contains null characters at random locations. I tried to create an iStringStream using this array (encodedData_arr) as below, I use this iStringStream to insert binary data(imagedata of Iplimage) to a MySQL database blob…
Morpheus
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How to remove null character (zero character) from string

I been trying to remove all the zero characters from my string My string is made from these hexadecimal bytes 00 44 00 65 00 6C 00 70 00 68 00 69 For every letter there is a Zero byte (null byte) in front of it.. I was guessing I had to use some…
SSpoke
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Char Array contains null characters before the end

I've got a class project to make a webserver in c++. Everything's been going OK until I got to the point where I needed to host images or pdfs, at which point the files were corrupted. Doing some more digging, I realized that all the corrupted…
Dr. Cyanide
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C++ - char array and the null character

I have two questions about char array. from the code bellow, since arr is const, why doesn't the compiler give me an error since I'm rewriting it? char arr[5]; // arr is a const pointer to (*)[5] array cin>>arr; // when I initialized a char…
AlexDan
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String with null-character

Suppose we have the two lexical definitions: lexical DQChr = ![\"] | [\"][\"]; lexical String = "\"" DQChr* "\""; Then the following cases parse well: parse(#String,"\"a\""); parse(#String,"\"\u0001\""); However, the null-character gives a…
Steven Klusener
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NULL characters in address for buffer overflow

I am trying to reproduce a buffer overflow. The address that I am trying to pass in has two null hex characters in it (i.e. 0x00547e00). There are also 4 more bytes that come after it (i.e 0x11111111 and 0x22222222). If I pass these in using gdb, it…
shawalli
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How can I handle string if null character in the middle of string?

I understand that string ends with a NULL. But if there is a null character(\0) in the middle of string, how can I handle the string? #include #include int main(){ char *str = "App\0le"; char *str2; printf("%c",…
Hwang
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fgets - Take null character into account

When scanning for user input using int scanf(const char *format, ...), I would read one less character than the string's size, because the last character of the string has to be the null character \0. char str[10]; scanf("%9s", str); /* take \0 into…
Andy Sukowski-Bang
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C++ reading lines of stream containing null character

I have the following problem- there is a file with information (I don't know the size of the file) like this: \0\0\0\0\0\0123456789\0\0\0\0\0\0Name \0\0\0\0\0\0111111111\0\0\0\0\0\0Name1 \0\0\0\0\0\0222222222\0\0\0\0\0\0Name2 and my goal is to read…
vtodorova
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Grep not working when null character exists and -z option used

My grep command is it: grep -Pzo -a 'Start(.*\n)*?.*?End' testfile.txt And testfile.txt contains: ItsTestStartFromHereEndNotVisibleStartFrom HereEndOkNotVisible the output: $ grep -Pzo -a 'Start(.*\n)*?.*?End'…
alihardan
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