term% ls -F
term% cat index.txt
DIRREAD(2)                    System Calls Manual                   DIRREAD(2)

       dirread, dirreadall - read directory

       #include <u.h>
       #include <libc.h>

       long dirread(int fd, Dir **buf)

       long dirreadall(int fd, Dir **buf)

       #define   STATMAX   65535U

       #define   DIRMAX    (sizeof(Dir)+STATMAX)

       The  data  returned  by  a  read(2) on a directory is a set of complete
       directory entries in a machine-independent format,  exactly  equivalent
       to  the  result of a stat(2) on each file or subdirectory in the direc‐
       tory.  Dirread decodes the directory entries into  a  machine-dependent
       form.   It  reads  from  fd  and  unpacks the data into an array of Dir
       structures whose address is returned in *buf (see stat(2) for the  lay‐
       out of a Dir).  The array is allocated with malloc(2) each time dirread
       is called.

       Dirreadall is like dirread, but reads in the entire directory; by  con‐
       trast, dirread steps through a directory one read(2) at a time.

       Directory  entries have variable length.  A successful read of a direc‐
       tory always returns an integral number of complete  directory  entries;
       dirread  always  returns complete Dir structures.  See read(5) for more

       The constant STATMAX is the maximum size that  a  directory  entry  can
       occupy.  The constant DIRMAX is an upper limit on the size necessary to
       hold a Dir structure and all the associated data.

       Dirread and dirreadall return the number of Dir  structures  filled  in
       buf.  The file offset is advanced by the number of bytes actually read.


       intro(2), open(2), read(2)

       Dirread and Dirreadall return zero for end of file and a negative value
       for error.  In either case, *buf is set  to  nil  so  the  pointer  can
       always be freed with impunity.

       These functions set errstr.