You can use sprintf to do it, or maybe snprintf if you have it: char str[ENOUGH]; sprintf(str, “%d”, 42); Where the number of characters (plus terminating char) in the str can be calculated using: (int)((ceil(log10(num))+1)*sizeof(char))
Read /usr/src/linux/Documentation/sysctl/kernel.txt. core_pattern is used to specify a core dumpfile pattern name. If the first character of the pattern is a ‘|’, the kernel will treat the rest of the pattern as a command to run. The core dump will be written to the standard input of that program instead of to a file. Instead … Read more
If you want to have a list of characters (a word), you can use char *word If you want a list of words (a sentence), you can use char **sentence If you want a list of sentences (a monologue), you can use char ***monologue If you want a list of monologues (a biography), you can … Read more
Stack Smashing here is actually caused due to a protection mechanism used by gcc to detect buffer overflow errors. For example in the following snippet: #include <stdio.h> void func() { char array[10]; gets(array); } int main(int argc, char **argv) { func(); } The compiler, (in this case gcc) adds protection variables (called canaries) which have … Read more
How to Run Valgrind Not to insult the OP, but for those who come to this question and are still new to Linux—you might have to install Valgrind on your system. sudo apt install valgrind # Ubuntu, Debian, etc. sudo yum install valgrind # RHEL, CentOS, Fedora, etc. sudo pacman -Syu valgrind # Arch, Manjaro, … Read more
Wow, everybody is such a pessimist around here. The answer is yes. It ain’t trivial: by the end, we’ll have the core function, a supporting struct, a wrapper function, and a macro around the wrapper function. In my work I have a set of macros to automate all this; once you understand the flow it’ll … Read more
The difference is that const char * is a pointer to a const char, while char * const is a constant pointer to a char. The first, the value being pointed to can’t be changed but the pointer can be. The second, the value being pointed at can change but the pointer can’t (similar to … Read more
To pass the ellipses on, you initialize a va_list as usual and simply pass it to your second function. You don’t use va_arg(). Specifically; void format_string(char *fmt,va_list argptr, char *formatted_string); void debug_print(int dbg_lvl, char *fmt, …) { char formatted_string[MAX_FMT_SIZE]; va_list argptr; va_start(argptr,fmt); format_string(fmt, argptr, formatted_string); va_end(argptr); fprintf(stdout, “%s”,formatted_string); }
There are two ways to split strings over multiple lines: Each string on its own line. Works only with strings: Plain C: char *my_string = “Line 1 ” “Line 2″; Objective-C: NSString *my_string = @”Line1 ” “Line2”; // the second @ is optional Using \ – can be used for any expression: Plain C: char … Read more
For int64_t type: #include <inttypes.h> int64_t t; printf(“%” PRId64 “\n”, t); for uint64_t type: #include <inttypes.h> uint64_t t; printf(“%” PRIu64 “\n”, t); you can also use PRIx64 to print in hexadecimal. cppreference.com has a full listing of available macros for all types including intptr_t (PRIxPTR). There are separate macros for scanf, like SCNd64. A typical … Read more