Hi, Why does this print garbage instead of exiting my program gracefully? I use system calls this way on BSD, and I wonder what would I need to make it work in Linux. int main(int argc, char **argv) { __asm ("movq $1,%rax; movq $0,%rdi; syscall"); /* exit(0) ? */ return 0; } Thanks. ...
for ex: i want to store output of system("dir"); Thanks & Regards, calvin ...
Hello, I have a performance issue in a bottleneck section in my code. Basically it's a simple nested loop. Profiling the issue reveals that the program spends a lot of time just incrementing both of the loop counters (++) and testing for termination (i/j < 8). Watching the assembly output I see that both counters don't get registers an...
I am looking for a C library that implements the server end of ssh. In particular, I am only interested in the subset that provides port forwarding. The ones that I have found so far (libssh2, NetSieben etc) seem to implement just the client. ...
Hello, I'm looking for a robust way to list the available serial (COM) ports on a Windows machine. There's this post about using WMI, but I would like something less .NET specific - I want to get the list of ports in a Python or a C++ program, without .NET. I currently know of two other approaches: Reading the information in the HARD...
For a simple project I have to make large numbers (e.g. 4294967123) readable, so I'm writing only the first digits with a prefix (4294967123 -> 4.29G, 12345 -> 12.34K etc.) The code (simplified) looks like this: const char* postfixes=" KMGT"; char postfix(unsigned int x) { return postfixes[(int) floor(log10(x))]; } It works, but...
Until now I have seen only tools and some information for the creation of Delphi code for a given C header file. However, in the 'Delphi first' case, there is a Delphi interface declaration and a generated DLL, and no C header. Are there tools which can extract the necessary information and build a C header file for a DLL? Such a tool ...
While in C-mode I can jump to a function using M-. on the function name....is there a way i can simply display the function prototype? (preferably as a tooltip or so) I often struggle to remember the exact order and types required by a given function. ...
Hi I have a very simple sprintf question. int STATUS = 0; char test[100]; int n = sprintf( test,"%04x", STATUS ); printf ("[%s] is a %d char long string\n",test,n); for(i=0 ; i<4 ; i++) { printf("%02x", test[i]); } printf("\n\n"); The output of this code is 30303030 which is not what I intend to have as output. Basi...
I'm trying to parse some input on an embedded system. I'm expecting something like this: SET VARNAME=1,2,3,4,5,6,7,8,9,10\0 When I'm converting the separate strings to ints, both atoi() and strtol() seem to be returning 0 if the string begins with 8. Here is my code: char *pch, *name, *vars; signed long value[256]; int i; #ifdef UA...
I'm sure some of you already experienced it. I have two linked lists of different types and I have two distinct functions that free the memory used by them. Those two functions are identical except for one thing. Generally a function that frees a list would looks like this: void free_list(T *p) { T *next; /* here */ while (p...
I am developing c on linux using vim and debugging using ddd. However I find that ddd performs very poorly at scrolling on this machine so its sometimes very frustrating to use. I like the way that ddd maps fairly closely to the gdb command set as this means I am free to use gdb commands when I choose, but using gdb itself is not an opt...
I think I've read somewhere that it is illegal to take the address of an enum value in C (enum values not being lvalues; however, I can't find any information on this now). Is that correct and, if so, why? Edit: Here's an example that clarifies what I mean by "enum value" above. I mean taking the address of first_value below, not tak...
Hello, I'm having a macro like this ( not exactly, but function is quite equivalent): #define STRUCTMEMBER(Member,Value) GlobalStructInstance. ## Member = Value ... STRUCTMEMBER(Item,1); This works perfectly in Visual C++, but gcc 3.4.5 (MingGW) yield the following error: pasting "." and "Item" does not give a valid preprocessing to...
I have a C function that contains all the code that will implement the bytecodes of a bytecode interpreter. I'm wondering if there is a way to align segments of the compiled code in memory on fixed size boundaries so that I could directly calculate the address to jump to from the value of the bytecode? Sort of the same way an array work...
Suppose the user inputs an infix expression as a string? What could be the easiest ( By easiest I mean the shortest) way to evaluate the result of that expression using C language? Probable ways are converting it to a postfix then by using stacks.But its rather a long process. Is there any way of using functions such as atoi() or eval()...
I want to learn C language (is this something good ?) and i didn't know from where i can download the language to my PC ? and are this FREE or must pay for ? ...
I'm curious: If you do a printf("%f", number); what is the precision of the statement? I.e. How many decimal places will show up? Is this compiler dependent? ...
I saw this post but didn't understand if this was the same issue. My database can be sorted on each column. Once the db is sorted, how do I maintain that order after my next query? For example: Order db by age: sprintf(sql, "select * from Customer_Table ORDER BY age_ID LIMIT 100 OFFSET %s;", offset); then the user looks at the...
Possible Duplicates: How can I get the size of an array from a pointer in C? Is there any way to determine the size of a C++ array programmatically? And if not, why? I get a pointer to a chunk of allocated memory out of a C style function. Now, it would be really interesting for debugging purposes to know how big the allocate...