readahead(2) System Calls Manual readahead(2) readahead - (libc -lc) #define _GNU_SOURCE /* feature_test_macros(7) */ #define _FILE_OFFSET_BITS 64 #include ssize_t readahead(int fd, off_t offset, size_t count); readahead() / ( ). fd . offset count . / offset (offset+count). readahead() . fd . readahead() 0 -1 errno . EBADF fd . EINVAL fd readahead() . 32 syscall(2). . 2.4.13 glibc 2.3. _FILE_OFFSET_BITS 64 readahead x86 ARM 32 off_t 32 . readahead() . . ext[234] . lseek(2), madvise(2), mmap(2), posix_fadvise(2), read(2) 3 . . : . 6.18 8 2026 readahead(2)