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diff --git a/reference/C/MAN/freopen.htm b/reference/C/MAN/freopen.htm new file mode 100644 index 0000000..90133d3 --- /dev/null +++ b/reference/C/MAN/freopen.htm @@ -0,0 +1,164 @@ +<TITLE>freopen</TITLE> +<body bgcolor="#ffffcc"> +<hr> +<pre> + + + +<h3>FOPEN(3) Linux Programmer's Manual FOPEN(3) +</h3> + +<h3>NAME +</h3> fopen, fdopen, freopen - stream open functions + +<h3>SYNOPSIS +</h3> #include <stdio.h> + + FILE *fopen( char *path, char *mode); + FILE *fdopen( int fildes, char *mode); + FILE *freopen( char *path, char *mode, FILE *stream); + +<h3>DESCRIPTION +</h3> The fopen function opens the file whose name is the string + pointed to by path and associates a stream with it. + + The argument mode points to a string beginning with one of + the following sequences (Additional characters may follow + these sequences.): + + r Open text file for reading. The stream is posi- + tioned at the beginning of the file. + + r+ Open for reading and writing. The stream is posi- + tioned at the beginning of the file. + + w Truncate file to zero length or create text file + for writing. The stream is positioned at the + beginning of the file. + + w+ Open for reading and writing. The file is created + if it does not exist, otherwise it is truncated. + The stream is positioned at the beginning of the + file. + + a Open for writing. The file is created if it does + not exist. The stream is positioned at the end of + the file. + + a+ Open for reading and writing. The file is created + if it does not exist. The stream is positioned at + the end of the file. + + The mode string can also include the letter ``b'' either + as a third character or as a character between the charac- + ters in any of the two-character strings described above. + This is strictly for compatibility with ANSI C3.159-1989 + (``ANSI C'') and has no effect; the ``b'' is ignored. + Linux may not behave this way. + + Any created files will have mode + S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH (0666), as + modified by the process' umask value (see umask(2). + + Reads and writes may be intermixed on read/write streams + in any order, and do not require an intermediate seek as + + + +<h3>BSD MANPAGE 29 November 1993 1 +</h3> + + + + +<h3>FOPEN(3) Linux Programmer's Manual FOPEN(3) +</h3> + + in previous versions of stdio. This is not portable to + other systems, however, and may not work under Linux + (someone should find out and fix this manpage); ANSI C + requires that a file positioning function intervene + between output and input, unless an input operation + encounters end-of-file. + + The fdopen function associates a stream with the existing + file descriptor, fildes. The mode of the stream must be + compatible with the mode of the file descriptor. + + The freopen function opens the file whose name is the + string pointed to by path and associates the stream + pointed to by stream with it. The original stream (if it + exists) is closed. The mode argument is used just as in + the fopen function. The primary use of the freopen func- + tion is to change the file associated with a standard text + stream (stderr, stdin, or stdout). + +<h3>RETURN VALUES +</h3> Upon successful completion fopen, fdopen and freopen + return a FILE pointer. Otherwise, NULL is returned and + the global variable errno is set to indicate the error. + +<h3>ERRORS +</h3> EINVAL The mode provided to fopen, fdopen, or freopen was + invalid. + + The fopen, fdopen and freopen functions may also fail and + set errno for any of the errors specified for the routine + malloc(3). + + The fopen function may also fail and set errno for any of + the errors specified for the routine open(2). + + The fdopen function may also fail and set errno for any of + the errors specified for the routine fcntl(2). + + The freopen function may also fail and set errno for any + of the errors specified for the routines open(2), + fclose(3) and fflush(3). + +</pre> +<hr> +<h3>SEE ALSO +</h3><p> +<a href=open.htm>open</a>, +<a href=fclose.htm>fclose</a>, +<pre> + +<h3>STANDARDS +</h3> The fopen and freopen functions conform to ANSI + C3.159-1989 (``ANSI C''). The fdopen function conforms to + IEEE Std1003.1-1988 (``POSIX''). + + + + + + + + +<h3>BSD MANPAGE 29 November 1993 2 +</h3> + +
</pre> +<P> +<hr> +<p> +<center> +<table border=2 width=80%> +<tr align=center> +<td width=25%> +<a href=../cref.html>Top</a> +</td><td width=25%> +<a href=../master_index.html>Master Index</a> +</td><td width=25%> +<a href=../SYNTAX/keywords.html>Keywords</a> +</td><td width=25%> +<a href=../FUNCTIONS/funcref.htm>Functions</a> +</td> +</tr> +</table> +</center> +<p> +<hr> + +This manual page was brought to you by <i>mjl_man V-2.0</i> |