alloc_pread
void *alloc_pread(int fd, off_t off, size_t len);
shdr = alloc_pread(ef->fd, ehdr->e_shoff, chunk);
shstr = alloc_pread(ef->fd, shdr[ehdr->e_shstrndx].sh_offset,
shdr = alloc_pread(ef.fd, ef.ehdr->e_shoff, size);
shstrtab = alloc_pread(ef.fd, shdr[ef.ehdr->e_shstrndx].sh_offset,
shdr = alloc_pread(ef->fd, (off_t)hdr->e_shoff, shdrbytes);