C / C++ Forum

I am working on this example from a book "C Primer Plus" by Prata 4th edition - p. 672. There is no erata on this problem at the publisher's website. 1) Is it a violation of copyright laws to post example code from a book to a newsgroup? 2) The program crashes as it tries to free memory and I would like to know the best way to correct...

Hello, I'm relatively new to C, although I've touched the subject several times for a couple of years. Tutorials etc. always taught me that I should use (in the beginning at least) cin and cout when outputting text to the screen. Recently, when giving C another shot with the new GCC 3.3, I couldn't use the functions defined in iostream.h...

Generally we have function names briefly indicating their actions. In similar lines I expected `fopen' mean "File Open", fgets "File Get String" etc. I was told recently this wasn't the case though with the above mentioned functions. `fgets' meant "Function Get String" similar to `fputc' ("Function Put Character") or `fgetc' ( "...

Hello experts! I question about understanding. I have read a book that says. If you have an array of integers you know that one element past the end of the array is legal as address but not to follow. That's ok. The address to one element past the end of the array is also grater then the address to the last element.That's also ok. The...

Hi look at the code below /* test.c */ int main(int argc, char *argv) { int *x; *x = 10; printf("%d\n", *x); return 0;

Hello, I'm very new to C. I have followed some of the earlier programs in the K&R book, but I am still far from even being a novice. For a long time I was looking for a little support group that I could come to for some guidance, it seems with this newsgroup I have found that. I've known usenet was the way to go, but when I started on my...

Hello I have seen in many source files the usage of extern +ACI-C+ACI-. What is its purpose? Thanks VRZ

Hi If I have a pointer to a some structure say for example payroll_ptr where struct payroll { ... } has some members and if i use a function argument as int function_process ( (payroll_ptr) 0 , ..) does the first argument become a NULL pointer ?

Hello, I am unaware whether this is the right group to ask. Please point me to another forum if required. I would like to replace a Fortran function by one which is written in C. The function shall provide the same interface for the fortran code calling the library. Fortunately, this works - currently under WinNT - well for all functions...

When assigning or testing equality between a type and a constant, should the constant be casted to the type? I.e. should fork() == -1 be written as fork() == (pid_t)-1? should uid = 45 be written as uid = (uid_t)45? Is the casting necessary? Does it increase portability? Browsing some projects, I noticed that -1 is casted but not other...

I'm trying to replace the characters in a pointer from an url string. Here is my code. // string has embedded '+', this code will not work. VOID PatchQuery(char *szQuery, char **ppszPatchedQuery) { char *p = szQuery; while (*p++)

I have dramatically improved my programming skills since becoming involved with clc, and this improvement is a direct result of my involvement with clc. Thanks to all. --Steve

Hi, I am new to c and use to program in basic before so i was wondering why this isn't working: char geturl(char *header, int client) { char *url; char *filename; char *tmpstring;

Hi, I am new to c and use to program in basic before so i was wondering why this isn't working: char geturl(char *header, int client) { char *url; char *filename; char *tmpstring;

Just a quickie: I heard that arrays declared in the global scope are automatically initialised with a block of zeros. To help with making my C source compatible with multiple compilers, I'd like to know if this is a proper ANSI-C thing or just another C++ quirk that only confuses people, if it's true at all. Thanks for your time, Koster.

Hi, how can I compare one character of a string to a char? I have tried this to compare the first character of directory to '/', but when I run this program I got a segmentation fault. void makeBaseDir( char * directory ) { if( *directory == '/' ) printf( "YES\n" );

Hello all, Say I have a file called "error.log" that I wish to send to the printer. How would I print the file to the printer? I found out I can use the SYSTEM function and send a command like PRINT error.log but that command is displayed on the screen which I don't want. I would rather use some sort of c rountine if possible. I am...

Hi all, I have attempted to implement a queue in C. So far all is well, but I have a question to ask you experts in regards to my implementation. Say I have a queue of integers. My queue will be an array of integers which could hold 100 elements for example.

Hello, Is there anyway to detect when scanf implicitly casts a value? If I have a scanf call which expects a float and is passed a double I believe that testing the scanf call with if(scanf("%f",&val) == 1) would be true, but the double would have been truncated to a float. Is there anyway to flag this cast? Thanks

Hi there, I am now having a puzzle regarding what a function call actually does when called. I have a simple code to see what's going on. It is simply calling another simple function from main(). The disassembled code for the function under linux (with gcc) looks like this: pushl %ebp ;push old %ebp movl ...

Hi I have a pointer to char and need to replace a string inside with another string. Something like that: char* str_replace(const char* oldString, const char* toBeReplaced, const char* replaceWith); How can I code the function if the string is of dynamic length?

I've been trying to perform a calculation that has been running into an underflow (insufficient precision) problem in Microsoft Excel, which calculates using at most 15 significant digits. For this purpose, that isn't enough. I was reading a book about some of the financial scandals of the 1990s called "Inventing Money: The Story of...

I understand the problem I'm having but am not sure how to fix it. My code passes two char* to a function which reads in some strings from a file and copies the contents into the two char*s. Now when my function returns, the values stored in the char* are some garbage values (perhaps because I didn't allocate any memory for them).. but even if...

Sorry for the re-post, but my previous question was left unanswered. I have a question about the appropriateness of calloc. Consider an array of pointers to structs which need to be allocated space on the heap, for example: typedef struct myStruct *PMYSTRUCT; struct myStruct { int i; int j;

Hi, Is there some way of using an array of strings? Like in basic? I know you have to create an array of chars so i think it has to be an 2d array or something... Really stuck here... Thanks in advance, Robert