.\" Automatically generated by Pod::Man v1.37, Pod::Parser v1.32 .\" .\" Standard preamble: .\" ======================================================================== .de Sh \" Subsection heading .br .if t .Sp .ne 5 .PP \fB\\$1\fR .PP .. .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. | will give a .\" real vertical bar. \*(C+ will give a nicer C++. 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If it receives any parameters, they are passed to \f(CW\*(C`FileHandle::open\*(C'\fR; if the open fails, the \f(CW\*(C`FileHandle\*(C'\fR object is destroyed. Otherwise, it is returned to the caller. .PP \&\f(CW\*(C`FileHandle::new_from_fd\*(C'\fR creates a \f(CW\*(C`FileHandle\*(C'\fR like \f(CW\*(C`new\*(C'\fR does. It requires two parameters, which are passed to \f(CW\*(C`FileHandle::fdopen\*(C'\fR; if the fdopen fails, the \f(CW\*(C`FileHandle\*(C'\fR object is destroyed. Otherwise, it is returned to the caller. .PP \&\f(CW\*(C`FileHandle::open\*(C'\fR accepts one parameter or two. With one parameter, it is just a front end for the built-in \f(CW\*(C`open\*(C'\fR function. With two parameters, the first parameter is a filename that may include whitespace or other special characters, and the second parameter is the open mode, optionally followed by a file permission value. .PP If \f(CW\*(C`FileHandle::open\*(C'\fR receives a Perl mode string (\*(L">\*(R", \*(L"+<\*(R", etc.) or a \s-1POSIX\s0 \fIfopen()\fR mode string (\*(L"w\*(R", \*(L"r+\*(R", etc.), it uses the basic Perl \f(CW\*(C`open\*(C'\fR operator. .PP If \f(CW\*(C`FileHandle::open\*(C'\fR is given a numeric mode, it passes that mode and the optional permissions value to the Perl \f(CW\*(C`sysopen\*(C'\fR operator. For convenience, \f(CW\*(C`FileHandle::import\*(C'\fR tries to import the O_XXX constants from the Fcntl module. If dynamic loading is not available, this may fail, but the rest of FileHandle will still work. .PP \&\f(CW\*(C`FileHandle::fdopen\*(C'\fR is like \f(CW\*(C`open\*(C'\fR except that its first parameter is not a filename but rather a file handle name, a FileHandle object, or a file descriptor number. .PP If the C functions \fIfgetpos()\fR and \fIfsetpos()\fR are available, then \&\f(CW\*(C`FileHandle::getpos\*(C'\fR returns an opaque value that represents the current position of the FileHandle, and \f(CW\*(C`FileHandle::setpos\*(C'\fR uses that value to return to a previously visited position. .PP If the C function \fIsetvbuf()\fR is available, then \f(CW\*(C`FileHandle::setvbuf\*(C'\fR sets the buffering policy for the FileHandle. The calling sequence for the Perl function is the same as its C counterpart, including the macros \f(CW\*(C`_IOFBF\*(C'\fR, \f(CW\*(C`_IOLBF\*(C'\fR, and \f(CW\*(C`_IONBF\*(C'\fR, except that the buffer parameter specifies a scalar variable to use as a buffer. \s-1WARNING:\s0 A variable used as a buffer by \f(CW\*(C`FileHandle::setvbuf\*(C'\fR must not be modified in any way until the FileHandle is closed or until \&\f(CW\*(C`FileHandle::setvbuf\*(C'\fR is called again, or memory corruption may result! .PP See perlfunc for complete descriptions of each of the following supported \f(CW\*(C`FileHandle\*(C'\fR methods, which are just front ends for the corresponding built-in functions: .PP .Vb 8 \& close \& fileno \& getc \& gets \& eof \& clearerr \& seek \& tell .Ve .PP See perlvar for complete descriptions of each of the following supported \f(CW\*(C`FileHandle\*(C'\fR methods: .PP .Vb 12 \& autoflush \& output_field_separator \& output_record_separator \& input_record_separator \& input_line_number \& format_page_number \& format_lines_per_page \& format_lines_left \& format_name \& format_top_name \& format_line_break_characters \& format_formfeed .Ve .PP Furthermore, for doing normal I/O you might need these: .IP "$fh\->print" 4 .IX Item "$fh->print" See \*(L"print\*(R" in perlfunc. .IP "$fh\->printf" 4 .IX Item "$fh->printf" See \*(L"printf\*(R" in perlfunc. .IP "$fh\->getline" 4 .IX Item "$fh->getline" This works like <$fh> described in \*(L"I/O Operators\*(R" in perlop except that it's more readable and can be safely called in a list context but still returns just one line. .IP "$fh\->getlines" 4 .IX Item "$fh->getlines" This works like <$fh> when called in a list context to read all the remaining lines in a file, except that it's more readable. It will also \fIcroak()\fR if accidentally called in a scalar context. .PP There are many other functions available since FileHandle is descended from IO::File, IO::Seekable, and IO::Handle. Please see those respective pages for documentation on more functions. .SH "SEE ALSO" .IX Header "SEE ALSO" The \fB\s-1IO\s0\fR extension, perlfunc, \&\*(L"I/O Operators\*(R" in perlop.