[PHP4BETA] some ?'s about reg.c

Can someone explain to me what the following piece of code from reg.c does? I figured the rest of it out, but I don't know when subs[0].rm_so would be equal to subs[0].rm_eo. Line 408 in reg.c: if (subs[0].rm_so == subs[0].rm_eo) { if (subs[0].rm_so + pos >= string_len) break; new_l = strlen (buf) + 1; if (new_l + 1 > buf_len) { buf_len = 1 + buf_len + 2 * new_l; nbuf = emalloc(buf_len * sizeof(char)); strcpy(nbuf, buf); efree(buf); buf = nbuf; } pos += subs[0].rm_eo + 1; buf [new_l-1] = string [pos-1]; buf [new_l] = '\0'; } else { pos += subs[0].rm_eo; } Thanks, -Andrey * Only 19,999 lines of C++ to my next ski trip... * -- PHP 4 Beta