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 values 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 corresponding  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 terminal.  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 corresponding 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  cur-
              rent working directory.  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 corresponding 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 directory.

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

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



GNU                                         1993-04-04                               FPATHCONF(3)