Back to index

glibc  2.9
Functions
fpathconf.c File Reference
#include <errno.h>
#include <stddef.h>
#include <unistd.h>
#include <limits.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/statvfs.h>
This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Functions

long int __fpathconf (int fd, int name)

Function Documentation

long int __fpathconf ( int  fd,
int  name 
)

Definition at line 31 of file fpathconf.c.

{
  if (fd < 0)
    {
      __set_errno (EBADF);
      return -1;
    }

  switch (name)
    {
    default:
      __set_errno (EINVAL);
      return -1;

    case _PC_LINK_MAX:
#ifdef LINK_MAX
      return LINK_MAX;
#else
      return -1;
#endif

    case _PC_MAX_CANON:
#ifdef MAX_CANON
      return MAX_CANON;
#else
      return -1;
#endif

    case _PC_MAX_INPUT:
#ifdef MAX_INPUT
      return MAX_INPUT;
#else
      return -1;
#endif

    case _PC_NAME_MAX:
#ifdef NAME_MAX
      {
       struct statfs buf;
       int save_errno = errno;

       if (__fstatfs (fd, &buf) < 0)
         {
           if (errno == ENOSYS)
             {
              __set_errno (save_errno);
              return NAME_MAX;
             }
           else if (errno == ENODEV)
             __set_errno (EINVAL);

           return -1;
         }
       else
         {
#ifdef _STATFS_F_NAMELEN
           return buf.f_namelen;
#else
# ifdef _STATFS_F_NAME_MAX
           return buf.f_name_max;
# else
           return NAME_MAX;
# endif
#endif
         }
      }
#else
      return -1;
#endif

    case _PC_PATH_MAX:
#ifdef PATH_MAX
      return PATH_MAX;
#else
      return -1;
#endif

    case _PC_PIPE_BUF:
#ifdef PIPE_BUF
      return PIPE_BUF;
#else
      return -1;
#endif

    case _PC_CHOWN_RESTRICTED:
#ifdef _POSIX_CHOWN_RESTRICTED
      return _POSIX_CHOWN_RESTRICTED;
#else
      return -1;
#endif

    case _PC_NO_TRUNC:
#ifdef _POSIX_NO_TRUNC
      return _POSIX_NO_TRUNC;
#else
      return -1;
#endif

    case _PC_VDISABLE:
#ifdef _POSIX_VDISABLE
      return _POSIX_VDISABLE;
#else
      return -1;
#endif

    case _PC_SYNC_IO:
#ifdef _POSIX_SYNC_IO
      return _POSIX_SYNC_IO;
#else
      return -1;
#endif

    case _PC_ASYNC_IO:
#ifdef _POSIX_ASYNC_IO
      {
       /* AIO is only allowed on regular files and block devices.  */
       struct stat64 st;

       if (__fxstat64 (_STAT_VER, fd, &st) < 0
           || (! S_ISREG (st.st_mode) && ! S_ISBLK (st.st_mode)))
         return -1;
       else
         return 1;
      }
#else
      return -1;
#endif

    case _PC_PRIO_IO:
#ifdef _POSIX_PRIO_IO
      return _POSIX_PRIO_IO;
#else
      return -1;
#endif

    case _PC_SOCK_MAXBUF:
#ifdef SOCK_MAXBUF
      return SOCK_MAXBUF;
#else
      return -1;
#endif

    case _PC_FILESIZEBITS:
#ifdef FILESIZEBITS
      return FILESIZEBITS;
#else
      /* We let platforms with larger file sizes overwrite this value.  */
      return 32;
#endif

    case _PC_REC_INCR_XFER_SIZE:
      /* XXX It is not entirely clear what the limit is supposed to do.
        What is incremented?  */
      return -1;

    case _PC_REC_MAX_XFER_SIZE:
      /* XXX It is not entirely clear what the limit is supposed to do.
        In general there is no top limit of the number of bytes which
        case be transported at once.  */
      return -1;

    case _PC_REC_MIN_XFER_SIZE:
      {
       /* XXX It is not entirely clear what the limit is supposed to do.
          I assume this is the block size of the filesystem.  */
       struct statvfs64 sv;

       if (__fstatvfs64 (fd, &sv) < 0)
         return -1;
       return sv.f_bsize;
      }

    case _PC_REC_XFER_ALIGN:
      {
       /* XXX It is not entirely clear what the limit is supposed to do.
          I assume that the number should reflect the minimal block
          alignment.  */
       struct statvfs64 sv;

       if (__fstatvfs64 (fd, &sv) < 0)
         return -1;
       return sv.f_frsize;
      }

    case _PC_ALLOC_SIZE_MIN:
      {
       /* XXX It is not entirely clear what the limit is supposed to do.
          I assume that the number should reflect the minimal block
          alignment.  */
       struct statvfs64 sv;

       if (__fstatvfs64 (fd, &sv) < 0)
         return -1;
       return sv.f_frsize;
      }

    case _PC_SYMLINK_MAX:
      /* In general there are no limits.  If a system has one it should
        overwrite this case.  */
      return -1;

    case _PC_2_SYMLINKS:
      /* Unix systems generally have symlinks.  */
      return 1;
    }
}

Here is the call graph for this function: