crash with musl c-library due to stack overflow in processes.c

[fabled]

In musl, ARG_MAX is defined as 131072 which seems to match linux kernel's definition of ARG_MAX.

processes.c in few places allocates "char cmdline[ARG_MAX];" buffers, and the default stack size of musl is about 80 kB, so the program crashes.

Allocating 100kB+ in stack sounds like a bad idea anyway. Perhaps use 4096 buffers always (as this is assumed if ARG_MAX is not defined). Alternatively, you could create the thread for processes.c with pthread_attr asking for sufficiently large stack.