Here's a very basic C snippet to open and read a file: int fd = open("test.txt",O_RDONLY); char buf[128]; int reader = read(fd,buf,128); int i; for (i=0;i<strlen(buf);i++) { printf("%i: I read: %c", i, (int)buf[i]); } I'm also including these standard headers: #include <stdio.h> #include <stdlib.h> #include <...
Hi! Is it posible to define a structure with a pointer to that type of structure? What I mean is: typedef struct { char* name; node* parent; } node; As far as I tried or read, I don't know how to do this or if it's even possible. ...
I've added a feature to my app that allows the user to save a business's contact details to the address book; however, to guard against adding multiple entries I want to check that the entry doesn't already exist. Any idea how to do this? The iPhone developer documentation seems a little unclear. I'm using the C api to add the contact. ...
I'm building a class wrapper for the mysql c api, specifically at the moment for mysql_real_escape_string and I don't think I'm doing it quite right. this is what I have for the function: std::string Database::EscapeString(const char *pStr) { char *tStr = new char[strlen(pStr)*2+1]; mysql_real_escape_string(m_sqlCon, tStr, pStr...
I have a pointer to my char array like this. unsigned char *recvBuf; recvBuf = (unsigned char *)malloc(sizeof(char)*RECVBUF); I then pass that to a function defined as void setHeader(MyHeader *myHeader, unsigned char *buffer) Which copies the first 12 bytes into a struct Then I try and pass it to another function later on ...
typedef struct unit_class_struct { char *name; } person; person * setName() { person * array; array = malloc (2 * sizeof(person)); array->name = strdup("Robert"); array++; array->name = strdup("Jose"); return array; } int main() { person *array; arra...
I've always been curious about audio conversion software, but I have never seen a proper explanation from a beginners point of view as to how to write a simple program that converts for example, a mp3 file to a wav. I'm not asking about any of the complex algorithms involved, just a small example using a simple library. Searching on SO, ...
I know in C you can declare a string and the number of characters like below, char mystring[50]; with '50' being the number of characters. However, what is proper procedure if the user is going to be inputting the contents of the string (via scanf("%s", mystring);)? Do I leave it as, char mystring[0]; leaving it as '0' since I ha...
Looking to write an SNMP and Netflow tool for Linux\BSD and seeking advice on language selection, C or Java. The tool will collect Netflows, send and recieve SNMP queries, connect to a Postgresql Databases and will be fronted by a web interface (PHP), in the future it will interface with devices using web services. Normally I would hav...
Text books say that & (addressof) operator doesn't apply to cannot be applied to expressions, constants, or register variables. Does constants mean only literals like 'A', '7' etc or variables declared with const keyword as well? I think this mean only literals since following code compiles:- int main() { const int i=10; const int *ip; ...
I am trying to pass a structure array pointer and a pointer to a structure array pointer into a function and then have it modified rather than using a return. This example code is indeed pointless, its just a learning example for me. Basically I want to create array[0]...array[1]..array[2] and so on and have a pointer that points to t...
If I have a function that returns a (char) in c and I have a (char* getSomething) how do I cast it? It is giving me an error when I try to cast it through either (char*) or (char*)& Example: If the function is : char* getSomething; getSomething = getSth(var); getSth return a char ...
I am looking for an efficient (optionally standard, elegant and easy to implement) solution to multiply relatively large numbers,and store the result into one or several integers : Let say I have two 64 bits integers declared like this : uint64_t a = xxx, b = yyy; When I do a*b, how can I detect if the operation result in an overflow...
I've been experimenting with emacs tempo mode and it seems likely to save me lots of typing (always a good thing), but I haven't gotten it to work exactly the way I want it. On the wiki, there is an example for elisp similar to what I want to do which works as expected. Here is the complete .emacs that I tested it on: (require 'tempo)...
The following code compiles on a C++ compiler. #include<cstdio> int main() { struct xx { int x; struct yy { char s; struct xx *p; }; struct yy *q; }; Would there be any difference in behavior while compiling with a C compiler? i.e. would there be any compiler error? ...
I want to compile / install the IP2Location Python extension found here: www.ip2location.com/python.aspx I tried following the instructions at these sites: eli.thegreenplace.net/2008/06/28/compiling-python-extensions-with-distutils-and-mingw/ boodebr.org/main/python/build-windows-extensions But I am getting no where. The pr...
I know this question has probably been asked in this forum many times and in the web as well. I am asked to create an implementation of a big integer in c++, however there is a constraint that one of my constructor should take an int as an argument... so I am guessing there will be more than one non-default constructor... so my question ...
How do I replicate the following Python code with the Python C API? class Sequence(): def __init__(self, max): self.max = max def data(self): i = 0 while i < self.max: yield i i += 1 So far, I have this: #include <Python/Python.h> #include <Python/structmember.h> /* Define a ne...
Is it possible to have a (fixed) array which stores its elements in the read-only segment of the executable and not on the stack? I came up with this code but unfortunately it is very unflexible when it comes to adding, moving or deleting items. How do I verify that the strings are indeed stored in the read-only segment? I tried readelf ...
in the following c code: char name[20]; int a; int b; for(i=0;i<10;i++) { printf("\nEnter name, a & b: "); scanf("%s %d %d",name,&a,&b); } does scanf read in the '\n', entered at the end of scanf() in 1st iteration, for the 2nd iteration inputs? ...