diff options
Diffstat (limited to 'man/man3/stdio.3')
-rw-r--r-- | man/man3/stdio.3 | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/man/man3/stdio.3 b/man/man3/stdio.3 new file mode 100644 index 0000000..45a8727 --- /dev/null +++ b/man/man3/stdio.3 @@ -0,0 +1,353 @@ +'\" t +.\" Copyright (c) 1990, 1991 Regents of the University of California. +.\" All rights reserved. +.\" +.\" SPDX-License-Identifier: BSD-4-Clause-UC +.\" +.\" @(#)stdio.3 6.5 (Berkeley) 5/6/91 +.\" +.\" Converted for Linux, Mon Nov 29 16:07:22 1993, faith@cs.unc.edu +.\" Modified, 2001-12-26, aeb +.\" +.TH stdio 3 2024-05-02 "Linux man-pages (unreleased)" +.SH NAME +stdio \- standard input/output library functions +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <stdio.h> +.P +.BI "FILE *" stdin ; +.BI "FILE *" stdout ; +.BI "FILE *" stderr ; +.fi +.SH DESCRIPTION +The standard I/O library provides a simple and efficient buffered stream +I/O interface. +Input and output is mapped into logical data streams and the +physical I/O characteristics are concealed. +The functions and macros are +listed below; more information is available from the individual man pages. +.P +A stream is associated with an external file (which may be a physical +device) by +.I opening +a file, which may involve creating a new file. +Creating an existing file +causes its former contents to be discarded. +If a file can support positioning requests (such as a disk file, +as opposed to a terminal), then a +.I file position indicator +associated with the stream is positioned at the start of the file (byte +zero), unless the file is opened with append mode. +If append mode is used, +it is unspecified whether the position indicator will be placed at the +start or the end of the file. +The position indicator is maintained by +subsequent reads, writes, and positioning requests. +All input occurs as if the characters were read by successive calls to the +.BR fgetc (3) +function; all output takes place as if all characters were written by +successive calls to the +.BR fputc (3) +function. +.P +A file is disassociated from a stream by +.I closing +the file. +Output streams are flushed (any unwritten buffer contents are +transferred to the host environment) before the stream is disassociated from +the file. +The value of a pointer to a +.I FILE +object is indeterminate after a file is closed (garbage). +.P +A file may be subsequently reopened, by the same or another program +execution, and its contents reclaimed or modified (if it can be +repositioned at the start). +If the main function returns to its original +caller, or the +.BR exit (3) +function is called, all open files are closed (hence all output streams are +flushed) before program termination. +Other methods of program termination, +such as +.BR abort (3) +do not bother about closing files properly. +.P +At program startup, three text streams are predefined and need not be +opened explicitly: +.I standard input +(for reading conventional input), +.I standard output +(for writing conventional output), and +.I standard error +(for writing diagnostic output). +These streams are abbreviated +.IR stdin , +.IR stdout , +and +.IR stderr . +When opened, the standard error stream is not fully buffered; the standard +input and output streams are fully buffered if and only if the streams do +not refer to an interactive device. +.P +Output streams that refer to terminal devices are always line buffered by +default; pending output to such streams is written automatically whenever +an input stream that refers to a terminal device is read. +In cases where a +large amount of computation is done after printing part of a line on an +output terminal, it is necessary to +.BR fflush (3) +the standard output before going off and computing so that the output will +appear. +.P +The +.I stdio +library is a part of the library +.B libc +and routines are automatically loaded as needed by +.BR cc (1). +The +SYNOPSIS +sections of the following manual pages indicate which include files are to +be used, what the compiler declaration for the function looks like and +which external variables are of interest. +.P +The following are defined as macros; these names may not be reused without +first removing their current definitions with +.BR #undef : +.BR BUFSIZ , +.BR EOF , +.BR FILENAME_MAX , +.BR FOPEN_MAX , +.BR L_cuserid , +.BR L_ctermid , +.BR L_tmpnam , +.BR NULL , +.BR SEEK_END , +.BR SEEK_SET , +.BR SEEK_CUR , +.BR TMP_MAX , +.BR clearerr , +.BR feof , +.BR ferror , +.BR fileno , +.\" Not on Linux: .BR fropen , +.\" Not on Linux: .BR fwopen , +.BR getc , +.BR getchar , +.BR putc , +.BR putchar , +.BR stderr , +.BR stdin , +.BR stdout . +Function versions of the macro functions +.BR feof , +.BR ferror , +.BR clearerr , +.BR fileno , +.BR getc , +.BR getchar , +.BR putc , +and +.B putchar +exist and will be used if the macros definitions are explicitly removed. +.SS List of functions +.TS +; +lb lbx +l l. +Function Description +_ +\fBclearerr\fP(3) T{ +check and reset stream status +T} +\fBfclose\fP(3) T{ +close a stream +T} +\fBfdopen\fP(3) T{ +stream open functions +T} +\fBfeof\fP(3) T{ +check and reset stream status +T} +\fBferror\fP(3) T{ +check and reset stream status +T} +\fBfflush\fP(3) T{ +flush a stream +T} +\fBfgetc\fP(3) T{ +get next character or word from input stream +T} +\fBfgetpos\fP(3) T{ +reposition a stream +T} +\fBfgets\fP(3) T{ +get a line from a stream +T} +\fBfileno\fP(3) T{ +return the integer descriptor of the argument stream +T} +\fBfmemopen\fP(3) T{ +open memory as stream +T} +\fBfopen\fP(3) T{ +stream open functions +T} +\fBfopencookie\fP(3) T{ +open a custom stream +T} +\fBfprintf\fP(3) T{ +formatted output conversion +T} +\fBfpurge\fP(3) T{ +flush a stream +T} +\fBfputc\fP(3) T{ +output a character or word to a stream +T} +\fBfputs\fP(3) T{ +output a line to a stream +T} +\fBfread\fP(3) T{ +binary stream input/output +T} +\fBfreopen\fP(3) T{ +stream open functions +T} +\fBfscanf\fP(3) T{ +input format conversion +T} +\fBfseek\fP(3) T{ +reposition a stream +T} +\fBfsetpos\fP(3) T{ +reposition a stream +T} +\fBftell\fP(3) T{ +reposition a stream +T} +\fBfwrite\fP(3) T{ +binary stream input/output +T} +\fBgetc\fP(3) T{ +get next character or word from input stream +T} +\fBgetchar\fP(3) T{ +get next character or word from input stream +T} +\fBgets\fP(3) T{ +get a line from a stream +T} +\fBgetw\fP(3) T{ +get next character or word from input stream +T} +\fBmktemp\fP(3) T{ +make temporary filename (unique) +T} +\fBopen_memstream\fP(3) T{ +open a dynamic memory buffer stream +T} +\fBopen_wmemstream\fP(3) T{ +open a dynamic memory buffer stream +T} +\fBperror\fP(3) T{ +system error messages +T} +\fBprintf\fP(3) T{ +formatted output conversion +T} +\fBputc\fP(3) T{ +output a character or word to a stream +T} +\fBputchar\fP(3) T{ +output a character or word to a stream +T} +\fBputs\fP(3) T{ +output a line to a stream +T} +\fBputw\fP(3) T{ +output a character or word to a stream +T} +\fBremove\fP(3) T{ +remove directory entry +T} +\fBrewind\fP(3) T{ +reposition a stream +T} +\fBscanf\fP(3) T{ +input format conversion +T} +\fBsetbuf\fP(3) T{ +stream buffering operations +T} +\fBsetbuffer\fP(3) T{ +stream buffering operations +T} +\fBsetlinebuf\fP(3) T{ +stream buffering operations +T} +\fBsetvbuf\fP(3) T{ +stream buffering operations +T} +\fBsprintf\fP(3) T{ +formatted output conversion +T} +\fBsscanf\fP(3) T{ +input format conversion +T} +\fBstrerror\fP(3) T{ +system error messages +T} +\fBsys_errlist\fP(3) T{ +system error messages +T} +\fBsys_nerr\fP(3) T{ +system error messages +T} +\fBtempnam\fP(3) T{ +temporary file routines +T} +\fBtmpfile\fP(3) T{ +temporary file routines +T} +\fBtmpnam\fP(3) T{ +temporary file routines +T} +\fBungetc\fP(3) T{ +un-get character from input stream +T} +\fBvfprintf\fP(3) T{ +formatted output conversion +T} +\fBvfscanf\fP(3) T{ +input format conversion +T} +\fBvprintf\fP(3) T{ +formatted output conversion +T} +\fBvscanf\fP(3) T{ +input format conversion +T} +\fBvsprintf\fP(3) T{ +formatted output conversion +T} +\fBvsscanf\fP(3) T{ +input format conversion +T} +.TE +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +C89, POSIX.1-2001. +.SH SEE ALSO +.BR close (2), +.BR open (2), +.BR read (2), +.BR write (2), +.BR stdout (3), +.BR unlocked_stdio (3) |