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diff --git a/man-pages-posix-2013/man3p/fdopen.3p b/man-pages-posix-2013/man3p/fdopen.3p new file mode 100644 index 0000000..cf1779e --- /dev/null +++ b/man-pages-posix-2013/man3p/fdopen.3p @@ -0,0 +1,194 @@ +'\" et +.TH FDOPEN "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. + +.SH NAME +fdopen +\(em associate a stream with a file descriptor +.SH SYNOPSIS +.LP +.nf +#include <stdio.h> +.P +FILE *fdopen(int \fIfildes\fP, const char *\fImode\fP); +.fi +.SH DESCRIPTION +The +\fIfdopen\fR() +function shall associate a stream with a file descriptor. +.P +The +.IR mode +argument is a character string having one of the following values: +.IP "\fIr\fP\ or\ \fIrb\fP" 14 +Open a file for reading. +.IP "\fIw\fP\ or\ \fIwb\fP" 14 +Open a file for writing. +.IP "\fIa\fP\ or\ \fIab\fP" 14 +Open a file for writing at end-of-file. +.IP "\fIr\fP+\ or\ \fIrb\fP+\ or\ \fIr\fP+\fIb\fP" 14 +Open a file for update (reading and writing). +.IP "\fIw\fP+\ or\ \fIwb\fP+\ or\ \fIw\fP+\fIb\fP" 14 +Open a file for update (reading and writing). +.IP "\fIa\fP+\ or\ \fIab\fP+\ or\ \fIa\fP+\fIb\fP" 14 +Open a file for update (reading and writing) at end-of-file. +.P +The meaning of these flags is exactly as specified in +\fIfopen\fR(), +except that modes beginning with +.IR w +shall not cause truncation of the file. +.P +Additional values for the +.IR mode +argument may be supported by an implementation. +.P +The application shall ensure that the mode of the stream as expressed +by the +.IR mode +argument is allowed by the file access mode of the open file +description to which +.IR fildes +refers. The file position indicator associated with the new stream is +set to the position indicated by the file offset associated with the +file descriptor. +.P +The error and end-of-file indicators for the stream shall be cleared. +The +\fIfdopen\fR() +function may cause the last data access timestamp of the underlying +file to be marked for update. +.P +If +.IR fildes +refers to a shared memory object, the result of the +\fIfdopen\fR() +function is unspecified. +.P +If +.IR fildes +refers to a typed memory object, the result of the +\fIfdopen\fR() +function is unspecified. +.P +The +\fIfdopen\fR() +function shall preserve the offset maximum previously set for the +open file description corresponding to +.IR fildes . +.SH "RETURN VALUE" +Upon successful completion, +\fIfdopen\fR() +shall return a pointer to a stream; otherwise, a null pointer shall be +returned and +.IR errno +set to indicate the error. +.SH ERRORS +The +\fIfdopen\fR() +function shall fail if: +.TP +.BR EMFILE +{STREAM_MAX} +streams are currently open in the calling process. +.P +The +\fIfdopen\fR() +function may fail if: +.TP +.BR EBADF +The +.IR fildes +argument is not a valid file descriptor. +.TP +.BR EINVAL +The +.IR mode +argument is not a valid mode. +.TP +.BR EMFILE +{FOPEN_MAX} +streams are currently open in the calling process. +.TP +.BR ENOMEM +Insufficient space to allocate a buffer. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +File descriptors are obtained from calls like +\fIopen\fR(), +\fIdup\fR(), +\fIcreat\fR(), +or +\fIpipe\fR(), +which open files but do not return streams. +.SH RATIONALE +The file descriptor may have been obtained from +\fIopen\fR(), +\fIcreat\fR(), +\fIpipe\fR(), +\fIdup\fR(), +\fIfcntl\fR(), +or +\fIsocket\fR(); +inherited through +\fIfork\fR(), +\fIposix_spawn\fR(), +or +.IR exec ; +or perhaps obtained by other means. +.P +The meanings of the +.IR mode +arguments of +\fIfdopen\fR() +and +\fIfopen\fR() +differ. With +\fIfdopen\fR(), +open for write (\fIw\fP or \fIw+\fP) does not truncate, and append +(\fIa\fP or \fIa+\fP) cannot create for writing. The +.IR mode +argument formats that include a \fIb\fP are allowed for consistency +with the ISO\ C standard function +\fIfopen\fR(). +The \fIb\fP has no effect on the resulting stream. Although not +explicitly required by this volume of POSIX.1\(hy2008, a good implementation of append (\fIa\fP) +mode would cause the O_APPEND flag to be set. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "Section 2.5.1" ", " "Interaction of File Descriptors and Standard I/O Streams", +.IR "\fIfclose\fR\^(\|)", +.IR "\fIfmemopen\fR\^(\|)", +.IR "\fIfopen\fR\^(\|)", +.IR "\fIopen\fR\^(\|)", +.IR "\fIopen_memstream\fR\^(\|)", +.IR "\fIposix_spawn\fR\^(\|)", +.IR "\fIsocket\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "\fB<stdio.h>\fP" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.unix.org/online.html . + +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |