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diff --git a/man3p/setvbuf.3p b/man3p/setvbuf.3p new file mode 100644 index 000000000..e5a14dd12 --- /dev/null +++ b/man3p/setvbuf.3p @@ -0,0 +1,91 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "SETVBUF" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" setvbuf +.SH NAME +setvbuf \- assign buffering to a stream +.SH SYNOPSIS +.LP +\fB#include <stdio.h> +.br +.sp +int setvbuf(FILE *restrict\fP \fIstream\fP\fB, char *restrict\fP \fIbuf\fP\fB, +int\fP \fItype\fP\fB, +.br +\ \ \ \ \ \ size_t\fP \fIsize\fP\fB); +.br +\fP +.SH DESCRIPTION +.LP +The \fIsetvbuf\fP() function may be used after the stream pointed +to by \fIstream\fP is associated with an open file but +before any other operation (other than an unsuccessful call to \fIsetvbuf\fP()) +is performed on the stream. The argument +\fItype\fP determines how \fIstream\fP shall be buffered, as follows: +.IP " *" 3 +{_IOFBF} shall cause input/output to be fully buffered. +.LP +.IP " *" 3 +{_IOLBF} shall cause input/output to be line buffered. +.LP +.IP " *" 3 +{_IONBF} shall cause input/output to be unbuffered. +.LP +.LP +If \fIbuf\fP is not a null pointer, the array it points to may be +used instead of a buffer allocated by \fIsetvbuf\fP() and +the argument \fIsize\fP specifies the size of the array; otherwise, +\fIsize\fP may determine the size of a buffer allocated by +the \fIsetvbuf\fP() function. The contents of the array at any time +are unspecified. +.LP +For information about streams, see \fIStandard I/O Streams\fP . +.SH RETURN VALUE +.LP +Upon successful completion, \fIsetvbuf\fP() shall return 0. Otherwise, +it shall return a non-zero value if an invalid value is +given for \fItype\fP or if the request cannot be honored, \ and +may set \fIerrno\fP to indicate the error. +.SH ERRORS +.LP +The \fIsetvbuf\fP() function may fail if: +.TP 7 +.B EBADF +The file descriptor underlying \fIstream\fP is not valid. +.sp +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +A common source of error is allocating buffer space as an "automatic" +variable in a code block, and then failing to close the +stream in the same block. +.LP +With \fIsetvbuf\fP(), allocating a buffer of \fIsize\fP bytes does +not necessarily imply that all of \fIsize\fP bytes are +used for the buffer area. +.LP +Applications should note that many implementations only provide line +buffering on input from terminal devices. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIStandard I/O Streams\fP , \fIfopen\fP() , \fIsetbuf\fP() , the +Base Definitions volume of IEEE\ Std\ 1003.1-2001, \fI<stdio.h>\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html . |