C :: Fscanf - Segmentation Fault For Larger Project
Apr 19, 2013
I added this snippet of code to a larger project I use to read some numbers in from a file, but for some reason I'm getting a segmentation fault.
Code:
printf("starting main
");
FILE *cutoffs;
double cut1=0, cut2=0, cut3=0;
printf("trying to open file
The cutoffs.in file looks something like
Code: 3.475 3.875 4.025
I ran the gdb debugger, so I know it is occurring at that fscanf; however, it doesn't give any other details (to be honest I don't have much experience with debuggers :x) ..The values are being put into an array. Before I just had numbers initialized in the array by hand, but need to have 20 different runs of this code with different numbers each time...
On compilation the following program does not give any error and when i run this program then sometimes it gives the segmentation fault. Specially with the larger values. I made sure that the values i inputted are not crossing any range of data types i used. I cannot get what is making my code to give segmentation fault error.
I am working on a distributed application in C. My program gives segmentation fault and aborts execution. But, when I try to run it through gdb, it keeps on running although without giving a useful output. I realize that I do not put much information in my query. But, what general causes could generate this behaviour. I am interested to find the cause of segmentation fault.
I can't understand why my program keeps on getting "Segmentation Fault". The last time I checked (in UBUNTU) it was already working, now I'm testing it in Windows and I keep on getting "Segmentation Fault".
I am using scientific linux. In the directory user/project/Build, after I ran 'make' to compile and link all the cpp files,I had no problems. But then, when I went to directory user/run/run.sh, which runs the project binary in user/project/Build/bin/project, I get a segmentation fault error. In the directory user/run, I enter 'gdb' in the command prompt and get the message "*** No targets specified and no makefile found. Stop." What am I supposed to do to detect the segmentation fault?
I get the segmentation fault whenever it tries to insert the first player.. however whenever i do this :
void MakeSquad(char type, string name, int coordX, int coordY, char dir, int squad) { GameSpace::MapSquadType MapOfSquads; MapOfSquads.insert(make_pair(name , Squad(squad)); // Squad( int ) just converts the int squad number to the Enum. }
The problem is probably the fact that I'm using the variable s in the wrong way, but as I'm very bad at C and C++, at least so far anyway, I've no clue what's wrong. Is it my size that I passed in the marked method?
Also, how do I tell it, later, once this starts to work, to pass the file name of the file it'll copy to as the first param and the file it reads from to the pipe as the second param?
I'm supposed to be reading from a file, and as I was given some code, but it's probably in C and not C++, even if it is, I'm still not that great at C++ either, but anyway, I'm to have the program read from the file and write to the pipe and have the child read from the pipe and write to the output file.
I have written a small program for a class to convert decimal to binary and the program itself works, however, I am storing the binary bits in a stack that is in a header file (which I have used successfully before). It appears to push the bits to the stack just fine, however, when I use the printStack function I get a segmentation fault.
Let say h(0)=01 and h(1)=10 and let say our first string is w=0 h(w)=01, h^2(w)=0110 h^3(w)=01101001..etc.
We have used h map, which is given in the program comment statement. Same thing, program is doing for three letters. These three letters we have passed as argument in h_i function. e.g. h_i(2,w,"a","d","g") function will apply the 3 letter map h(definition is given in commented form in program) 2 times on string w.
In program w=a; and three letters are a, d and g. /* h(a)=abcab,h(b)=acabcb,h(c)=acbcacb */ here b=d and c=g.
Above program gives core dump at free(w2) free(w1). if we remove these free statements then it gives correct answer. But, we want to free w1 and w2 in the above code. How can we make free both w1 and w2 strings?
I want to know what was wrong with my code when I submitted. It's a Traveling Salesperson Problem, and the code is complete for the most part. I just can't seem to find what's causing the segmentation fault even after attempting to debug with gdb. Something is supposed to be wrong with line 76, but I don't see how my arrays are messing up. I've looked through this code countless times, and I know I'm just missing something small. I just don't want to end up making whatever mistake I made on this again in the future.
I have a problem in my code and after hours of looking I really cannot find out what is the problem.I use scanf to to parse lines of a file, let me copy only the important part:
Code:
/*File read...everything is fine*/ int seq_1, seq_i2; int len; while(fgets(&line[strlen(line)], line_length, file)!= NULL) { }
[code]....
if (num_sc ==4) //the wanted format, do something So I am allocating all variables, and giving to sscanf pointers, so I really don't get where the segmentation fault appears.I checked with the debugger, the first line of the file is read, but at the second it crashes at the line of sscanf! The two lines don't have the format I want in sscanf but therefore I check if this number is 4 and then do other stuff to the data...
It is suppose to display the message "This Account ID does not exist" but why do I get "segmentation fault"??I was able to compile and run the program so it shouldn't be a problem of the compiler.
i'm writing a C code, can it can be compiled, however everytime I run this program, after I typed in the number the system will show Segmentation fault (core dumped).
Write a program that reads in the names and the ages of ten people. Store these data in two arrays (make sure that the entered names are not longer than the array size you choose). Then produce a table of ten lines, with each line giving the name and age of a person along with the (positive or negative) deviation of that person's age from the average age. The code I wrote to fill in the arrays looks as follows
Code: #include<stdlib.h> #include<stdio.h> int main() { // begin main() // array length
[Code]....
When I compile it, it gives me warnings that few of the variables I declared aren't used, but that is not affecting the program at all. When I run the program, it allows me to pass the names and ages into the arrays, but when it comes to displaying them, I'm getting a 'Segmentation fault'. I used very similar code in Java to write the program, and it worked fine so what is the problem with C then?
i want to enter a URL in as a string, and extract just the URL part.
eg: Code: input: URL....
output: URL....
Input: URL.... output: URL.... part of our header file which we cannot edit (the url is always less than 140 characters):
Code:
char url[140]; function i am having problems with Code: void init_url(char new_url[]) { /* This function sets the variable url to new_url and url_size to the number of characters in the url It also initializes url_error_flag }
[code]....
whenever i try a URL like the second one above with no '?' i'm getting a segmentation fault error which is becase i'm trying to access an invalid index. i'm not sure what an array is initialized to when i do not explicitly assign it anything, for example
Code:
char values[140] = {0};
i've read it depends on whether it is a global vs local array or something? i know this could all be fixed with simply assigning the array values to 0 but i'm not allowed to edit the header file.
For some reason when i put cout<<endl i'm getting segmentation faults in my Parser code. It's really weird some inputs of strings using cout is already faulting. However sometimes printf doesn't fault, but sometimes it will, it seems really unstable.
The court can basically be anywhere in the Parse(string) function, i have a cout at line 254 which faults.
I have created a multimap for my road points. The key refers to the road number and the values are vec3 points that make up the road.
I am trying to iterate through the values of each key point and create a road segment at each point on the road (except the last), adjust the values to be on the road points and then store them in a std::vector.
The RoadSegment constructor creates 6 vec3 points and pushes them onto a std::vector.
I have a segmentation fault in the line marked in bold [for(mapIt = it.first; mapIt != it.second; ++mapIt)]
When i take out the lines creating the new objects and pushing them onto the std::vector it works fine.
std::vector<glm::vec3>::iterator SegIt; for(int i = 0; i < m_genRoads->getKeyValueData().size(); i++) { int numberDesired = m_genRoads->getMultimapData().count(i) - 1;
I have a little problem with my Qt-5 Program by using a QList-Object. If I call QList::isEmpty or ::size, my program stops and I receive a Segmentation-fault (SIGSEGV), but I cannot explain this error to me. So, I don't see any errors in my code.
m_pGraph->getNodes returns a list of SGraphNode-Objects which contain the problematic list.
If I step in the QList-object, I also see that the member "d" in the QList has a very low value (between 0x00 and 0x11)..
After emitting the SIGSEGV, the debugger jumps into qlist.h, line 93 (inline bool isEmpty() const { return d->end == d->begin; }), but there is no more Information given by the Debugger.
