Home Man
Search
Today's Posts
Register

Linux & Unix Commands - Search Man Pages

RedHat 9 (Linux i386) - man page for stdio (redhat section 3)

STDIO(3)			    Linux Programmer's Manual				 STDIO(3)

NAME
       stdio - standard input/output library functions

SYNOPSIS
       #include <stdio.h>

       FILE *stdin;
       FILE *stdout;
       FILE *stderr;

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.

       A stream is associated with an external file (which may be a physical device) by 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 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, the position indicator will be placed the end-of-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 fgetc(3) function;
       all output takes place as if all characters were read by successive calls to the  fputc(3)
       function.

       A  file	is  disassociated  from a stream by 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 FILE object is indeterminate
       after a file is closed (garbage).

       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 exit(3) function is called, all open files
       are closed (hence all output streams are flushed) before program termination.  Other meth-
       ods of program termination, such as abort(3) do not bother about closing files properly.

       At program startup, three text streams are predefined and need not be opened explicitly --
       standard  input	(for reading conventional input), -- standard output (for writing conven-
       tional input), and standard error (for writing  diagnostic  output).   These  streams  are
       abbreviated  stdin,stdout and 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 to refer to an interactive device.

       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 fflush(3)  the  standard
       output before going off and computing so that the output will appear.

       The  stdio  library is a part of the library libc and routines are automatically loaded as
       needed by the compilers cc(1) and pc(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.

       The following are defined as macros; these names may not be re-used without first removing
       their  current  definitions  with #undef: BUFSIZ, EOF, FILENAME_MAX, FOPEN_MAX, L_cuserid,
       L_ctermid, L_tmpnam, NULL, SEEK_END, SEEK_SET, SEE_CUR, TMP_MAX, clearerr,  feof,  ferror,
       fileno,	fropen,  fwopen,  getc,  getchar, putc, putchar, stderr, stdin, stdout.  Function
       versions of the macro functions feof, ferror, clearerr, fileno, getc, getchar,  putc,  and
       putchar exist and will be used if the macros definitions are explicitly removed.

LIST OF FUNCTIONS
       Function  Description

       clearerr  check and reset stream status

       fclose	 close a stream

       fdopen	 stream open functions

       feof	 check and reset stream status

       ferror	 check and reset stream status

       fflush	 flush a stream

       fgetc	 get next character or word from input stream

       fgetpos	 reposition a stream

       fgets	 get a line from a stream

       fileno	 check and reset stream status

       fopen	 stream open functions

       fprintf	 formatted output conversion

       fpurge	 flush a stream

       fputc	 output a character or word to a stream

       fputs	 output a line to a stream

       fread	 binary stream input/output

       freopen	 stream open functions

       fropen	 open a stream

       fscanf	 input format conversion

       fseek	 reposition a stream

       fsetpos	 reposition a stream

       ftell	 reposition a stream

       fwrite	 binary stream input/output

       getc	 get next character or word from input stream

       getchar	 get next character or word from input stream

       gets	 get a line from a stream

       getw	 get next character or word from input stream

       mktemp	 make temporary file name (unique)

       perror	 system error messages

       printf	 formatted output conversion

       putc	 output a character or word to a stream

       putchar	 output a character or word to a stream

       puts	 output a line to a stream

       putw	 output a character or word to a stream

       remove	 remove directory entry

       rewind	 reposition a stream

       scanf	 input format conversion

       setbuf	 stream buffering operations

       setbuffer stream buffering operations

       setlinebuf
		 stream buffering operations

       setvbuf	 stream buffering operations

       sprintf	 formatted output conversion

       sscanf	 input format conversion

       strerror  system error messages

       sys_errlist
		 system error messages

       sys_nerr  system error messages

       tempnam	 temporary file routines

       tmpfile	 temporary file routines

       tmpnam	 temporary file routines

       ungetc	 un-get character from input stream

       vfprintf  formatted output conversion

       vfscanf	 input format conversion

       vprintf	 formatted output conversion

       vscanf	 input format conversion

       vsprintf  formatted output conversion

       vsscanf	 input format conversion

CONFORMING TO
       The stdio library conforms to ANSI X3.159-1989 (``ANSI C'').

SEE ALSO
       open(2), close(2), read(2), write(2), stdout(3)

					    2001-12-26					 STDIO(3)


All times are GMT -4. The time now is 07:52 PM.

Unix & Linux Forums Content Copyrightę1993-2018. All Rights Reserved.
UNIX.COM Login
Username:
Password:  
Show Password