Redirect stdout/stderr to NSLog on iOS Simulator

main.m

#include <unistd.h>

static int redirect_nslog(const char *prefix, const char *buffer, int size)
{
    NSLog(@"%s (%d bytes): %.*s", prefix, size, size, buffer);
    return size;
}

static int stderr_redirect_nslog(void *inFD, const char *buffer, int size)
{
    return redirect_nslog("stderr", buffer, size);
}

static int stdout_redirect_nslog(void *inFD, const char *buffer, int size)
{
    return redirect_nslog("stdout", buffer, size);
}

int main(int argc, char *argv[])
{
    setlinebuf(stdout);
    setlinebuf(stderr);
    stdout->_write = stdout_redirect_nslog;
    stderr->_write = stderr_redirect_nslog;
    /* ... */
}