diff options
Diffstat (limited to 'src/wc.c')
| -rw-r--r-- | src/wc.c | 6 |
1 files changed, 6 insertions, 0 deletions
@@ -29,6 +29,7 @@ #include "system.h" #include "argv-iter.h" #include "error.h" +#include "fadvise.h" #include "mbchar.h" #include "physmem.h" #include "quote.h" @@ -211,6 +212,10 @@ wc (int fd, char const *file_x, struct fstatus *fstatus) } count_complicated = print_words || print_linelength; + /* Advise the kernel of our access pattern only if we will read(). */ + if (!count_bytes || count_chars || print_lines || count_complicated) + fdadvise (fd, 0, 0, FADVISE_SEQUENTIAL); + /* When counting only bytes, save some line- and word-counting overhead. If FD is a `regular' Unix file, using lseek is enough to get its `size' in bytes. Otherwise, read blocks of BUFFER_SIZE @@ -238,6 +243,7 @@ wc (int fd, char const *file_x, struct fstatus *fstatus) } else { + fdadvise (fd, 0, 0, FADVISE_SEQUENTIAL); while ((bytes_read = safe_read (fd, buf, BUFFER_SIZE)) > 0) { if (bytes_read == SAFE_READ_ERROR) |