打印char时printf的奇怪行为-LLDB调试器

Question

While working with a static C++ library for my iOS Xcode project, I met a strange behavior with printf and Xcode LLDB debugger, sometimes my print results of printf("%s", char*) was the char concatenated with numbers or garbage characters. The attached image speaks for itself. Any idea?

Answer 1

Seems to work as expected. %s requires NUL-terminated string, that is, for a given char* , print anything until the first '\\0' . You have to allocate 5 bytes and assign a[4]=0; if you want your array to be suitable for %s .

Answer 2

The character array a needs to be terminated with a '\\0' if you're printing it with a %s format specifier:

char * a = new char[5];

a[0] = 'i';
a[1] = 'p';
a[2] = 'o';
a[3] = 'd';
a[4] = '\0';

printf("word: %s\n", a);