FPATHCONF(3)        Linux Programmer's Manual        FPATHCONF(3)

NAME
       fpathconf, pathconf - get configuration values for files

SYNOPSIS
       #include <unistd.h>

       long fpathconf(int filedes, int name);
       long pathconf(char *path, int name);

DESCRIPTION
       fpathconf() gets a value for the configuration option name
       for the open file descriptor filedes.

       pathconf() gets a value for configuration option name  for
       the file name path.

       The corresponding macros defined in <unistd.h> are minimum
       values; if an application wants to take advantage of  val-
       ues  which may change, a call to fpathconf() or pathconf()
       can be made, which may yield more liberal results.

       Setting name equal  to  one  of  the  following  constants
       returns the following configuration options:

       _PC_LINK_MAX
              returns  the  maximum  number of links to the file.
              If filedes or path refer to a directory,  then  the
              value  applies  to the whole directory.  The corre-
              sponding macro is _POSIX_LINK_MAX.

       _PC_MAX_CANON
              returns the maximum length  of  a  formatted  input
              line,  where filedes or path must refer to a termi-
              nal.  The corresponding macro is  _POSIX_MAX_CANON.

       _PC_MAX_INPUT
              returns  the maximum length of an input line, where
              filedes or path must refer to a terminal.  The cor-
              responding macro is _POSIX_MAX_INPUT.

       _PC_NAME_MAX
              returns  the  maximum  length  of a filename in the
              directory path or filedes.  the process is  allowed
              to    create.     The    corresponding   macro   is
              _POSIX_NAME_MAX.

       _PC_PATH_MAX
              returns the maximum length of a  relative  pathname
              when  path or filedes is the current working direc-
              tory.  The corresponding macro is  _POSIX_PATH_MAX.

       _PC_PIPE_BUF
              returns  the size of the pipe buffer, where filedes
              must refer to a pipe or FIFO and path must refer to
              a FIFO. The corresponding macro is _POSIX_PIPE_BUF.

       _PC_CHOWN_RESTRICTED
              returns nonzero if the chown(2)  call  may  not  be
              used  on  this file.  If filedes or path refer to a
              directory, then this applies to all files  in  that
              directory.      The    corresponding    macro    is
              _POSIX_CHOWN_RESTRICTED.

       _PC_NO_TRUNC
              returns nonzero if accessing filenames longer  than
              _POSIX_NAME_MAX  generates  an  error.   The corre-
              sponding macro is _POSIX_NO_TRUNC.

       _PC_VDISABLE
              returns nonzero if special character processing can
              be  disabled, where filedes or path must refer to a
              terminal.

RETURN VALUE
       The limit is returned, if one exists.  If the system  does
       not  have  a  limit  for  the  requested  resource,  -1 is
       returned, and errno is unchanged.  If there is  an  error,
       -1  is returned, and errno is set to reflect the nature of
       the error.

CONFORMING TO
       POSIX.1

NOTES
       Files with name lengths longer than the value returned for
       name  equal  to _PC_NAME_MAX may exist in the given direc-
       tory.

       Some returned values may be huge; they  are  not  suitable
       for allocating memory.

SEE ALSO
       getconf(1), statfs(2), open(2), sysconf(3)

GNU                       April 4, 1993                         1