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diff --git a/man3/mkfifo.3 b/man3/mkfifo.3 new file mode 100644 index 0000000..f43f07d --- /dev/null +++ b/man3/mkfifo.3 @@ -0,0 +1,202 @@ +'\" t +.\" This manpage is Copyright (C) 1995 James R. Van Zandt <jrv@vanzandt.mv.com> +.\" and Copyright (C) 2006, 2014 Michael Kerrisk +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.\" changed section from 2 to 3, aeb, 950919 +.\" +.TH mkfifo 3 2023-07-20 "Linux man-pages 6.05.01" +.SH NAME +mkfifo, mkfifoat \- make a FIFO special file (a named pipe) +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <sys/types.h> +.B #include <sys/stat.h> +.PP +.BI "int mkfifo(const char *" pathname ", mode_t " mode ); +.PP +.BR "#include <fcntl.h> " "/* Definition of AT_* constants */" +.B #include <sys/stat.h> +.PP +.BI "int mkfifoat(int " dirfd ", const char *" pathname ", mode_t " mode ); +.fi +.PP +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.PP +.BR mkfifoat (): +.nf + Since glibc 2.10: + _POSIX_C_SOURCE >= 200809L + Before glibc 2.10: + _ATFILE_SOURCE +.fi +.SH DESCRIPTION +.BR mkfifo () +makes a FIFO special file with name \fIpathname\fP. +\fImode\fP specifies the FIFO's permissions. +It is modified by the +process's \fBumask\fP in the usual way: the permissions of the created +file are \fB(\fP\fImode\fP\fB & \[ti]umask)\fP. +.PP +A FIFO special file is similar to a pipe, except that it is created +in a different way. +Instead of being an anonymous communications +channel, a FIFO special file is entered into the filesystem by +calling +.BR mkfifo (). +.PP +Once you have created a FIFO special file in this way, any process can +open it for reading or writing, in the same way as an ordinary file. +However, it has to be open at both ends simultaneously before you can +proceed to do any input or output operations on it. +Opening a FIFO for reading normally blocks until some +other process opens the same FIFO for writing, and vice versa. +See +.BR fifo (7) +for nonblocking handling of FIFO special files. +.SS mkfifoat() +The +.BR mkfifoat () +function operates in exactly the same way as +.BR mkfifo (), +except for the differences described here. +.PP +If the pathname given in +.I pathname +is relative, then it is interpreted relative to the directory +referred to by the file descriptor +.I dirfd +(rather than relative to the current working directory of +the calling process, as is done by +.BR mkfifo () +for a relative pathname). +.PP +If +.I pathname +is relative and +.I dirfd +is the special value +.BR AT_FDCWD , +then +.I pathname +is interpreted relative to the current working +directory of the calling process (like +.BR mkfifo ()). +.PP +If +.I pathname +is absolute, then +.I dirfd +is ignored. +.PP +See +.BR openat (2) +for an explanation of the need for +.BR mkfifoat (). +.SH RETURN VALUE +On success +.BR mkfifo () +and +.BR mkfifoat () +return 0. +On error, \-1 is returned and +.I errno +is set to indicate the error. +.SH ERRORS +.TP +.B EACCES +One of the directories in \fIpathname\fP did not allow search +(execute) permission. +.TP +.B EBADF +.RB ( mkfifoat ()) +.I pathname +is relative but +.I dirfd +is neither +.B AT_FDCWD +nor a valid file descriptor. +.TP +.B EDQUOT +The user's quota of disk blocks or inodes on the filesystem has been +exhausted. +.TP +.B EEXIST +\fIpathname\fP already exists. +This includes the case where +.I pathname +is a symbolic link, dangling or not. +.TP +.B ENAMETOOLONG +Either the total length of \fIpathname\fP is greater than +\fBPATH_MAX\fP, or an individual filename component has a length +greater than \fBNAME_MAX\fP. +In the GNU system, there is no imposed +limit on overall filename length, but some filesystems may place +limits on the length of a component. +.TP +.B ENOENT +A directory component in \fIpathname\fP does not exist or is a +dangling symbolic link. +.TP +.B ENOSPC +The directory or filesystem has no room for the new file. +.TP +.B ENOTDIR +A component used as a directory in \fIpathname\fP is not, in fact, a +directory. +.TP +.B ENOTDIR +.RB ( mkfifoat ()) +.I pathname +is a relative pathname and +.I dirfd +is a file descriptor referring to a file other than a directory. +.TP +.B EROFS +\fIpathname\fP refers to a read-only filesystem. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR mkfifo (), +.BR mkfifoat () +T} Thread safety MT-Safe +.TE +.sp 1 +.SH VERSIONS +It is implemented using +.BR mknodat (2). +.SH STANDARDS +POSIX.1-2008. +.SH HISTORY +.TP +.BR mkfifo () +POSIX.1-2001. +.TP +.BR mkfifoat () +glibc 2.4. +POSIX.1-2008. +.SH SEE ALSO +.BR mkfifo (1), +.BR close (2), +.BR open (2), +.BR read (2), +.BR stat (2), +.BR umask (2), +.BR write (2), +.BR fifo (7) |