man3/mkfifoat.3

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  26 .TH MKFIFOAT 3 2006-04-06 "Linux 2.6.16" "Linux Programmer's Manual"
  27 .SH NAME
  28 mkfifoat \- make a FIFO (named pipe) relative to a directory file descriptor
  29 .SH SYNOPSIS
  30 .nf
  31 .B #include <sys/stat.h>
  32 .sp
  33 .BI "int mkfifoat(int " dirfd ", const char *" pathname ", mode_t " mode );
  34 .fi
  35 .SH DESCRIPTION
  36 The
  37 .BR mkfifoat ()
  38 system call operates in exactly the same way as
  39 .BR mkfifo (3),
  40 except for the differences described in this manual page.
  41
  42 If the pathname given in
  43 .I pathname
  44 is relative, then it is interpreted relative to the directory
  45 referred to by the file descriptor
  46 .IR dirfd
  47 (rather than relative to the current working directory of
  48 the calling process, as is done by
  49 .BR mkfifo (3)
  50 for a relative pathname).
  51
  52 If the pathname given in
  53 .I pathname
  54 is relative and
  55 .I dirfd
  56 is the special value
  57 .BR AT_FDCWD ,
  58 then
  59 .I pathname
  60 is interpreted relative to the current working
  61 directory of the calling process (like
  62 .BR mkfifo (3)).
  63
  64 If the pathname given in
  65 .IR pathname
  66 is absolute, then
  67 .I dirfd
  68 is ignored.
  69 .SH "RETURN VALUE"
  70 On success,
  71 .BR mkfifoat ()
  72 returns 0.
  73 On error, \-1 is returned and
  74 .I errno
  75 is set to indicate the error.
  76 .SH ERRORS
  77 The same errors that occur for
  78 .BR mkfifo (3)
  79 can also occur for
  80 .BR mkfifoat ().
  81 The following additional errors can occur for
  82 .BR mkfifoat ():
  83 .TP
  84 .B EBADF
  85 .I dirfd
  86 is not a valid file descriptor.
  87 .TP
  88 .B ENOTDIR
  89 .I pathname
  90 is a relative path and
  91 .I dirfd
  92 is a file descriptor referring to a file other than a directory.
  93 .SH NOTES
  94 See
  95 .BR openat (2)
  96 for an explanation of the need for
  97 .BR mkfifoat ().
  98 .SH "CONFORMING TO"
  99 This system call is non-standard but is proposed
 100 for inclusion in a future revision of POSIX.1.
 101 .SH VERSIONS
 102 .BR mkfifoat ()
 103 was added to glibc in version 2.4.
 104 It is implemented using
 105 .BR mknod (2),
 106 available on Linux since kernel 2.6.16.
 107 .SH "SEE ALSO"
 108 .BR openat (2),
 109 .BR path_resolution (2),
 110 .BR mkfifo (3).