The base class for all other IO handle classes. Its main purpose is for the other IO classes to inherit from it; programs should not create IO::Handle objects directly. Provides the following methods.
new |
new
Constructor. Creates a new IO::Handle object.
new_from_fd |
new_from_fd (fd, mode)
Constructor. Like new, creates an IO::Handle object. It requires two parameters, which are passed to the method fdopen; if fdopen fails, the object is destroyed. Otherwise, it is returned to the caller.
clearerr |
$fh->clearerr
Clears the given handle's error indicator.
error |
$fh->error
Returns true if the given handle has experienced any errors since it was opened or since the last call to clearerr.
fdopen |
$fh->fdopen (fd, mode)
Like an ordinary open except that the first parameter is a filehandle name, an IO::Handle object, or a file descriptor number.
flush |
$fh->flush
Flushes the given handle's buffer.
getline |
$fh->getline
Works like <$fh>, described in the section on "I/O Operators" in the perlop manpage, but is more readable and can be safely called in an array context, while still returning one line.
getlines |
$fh->getlines
Works like <$fh> when called in an array context to read all the remaining lines in a file, but is more readable. croak s if called in scalar context.
opened |
$fh->opened
Returns true if the object is currently a valid file descriptor.
ungetc |
$fh->ungetc (ord)
Pushes a character with the ordinal value ord back onto the given handle's input stream.
untaint |
$fh->untaint
Special method for working under -T and setuid/gid scripts. Marks the object as taint-clean, and as such, data read from it is also considered taint-clean.
write |
$fh->write (buf, len[, offset])
Like write found in C; that is, the opposite of read. The wrapper for the Perl write function is format_write.
IO::Handle also provides the following methods, which are not described in detail here because they are simply frontends for the corresponding built-in functions. See Chapter 5, "Function Reference" for more information.
Method |
Description |
---|---|
close |
Closes file or pipe |
eof |
Returns 1 if next read will return end-of-file |
fileno |
Returns file descriptor for a filehandle |
getc |
Returns next character from input file |
|
Prints a string or comma-separated list of strings |
printf |
Prints a formatted string |
read |
Reads data from a filehandle |
stat |
Returns an array of status information for a file |
sysread |
Reads data from a filehandle with system call read(2) |
syswrite |
Writes data to a filehandle with system call write(2) |
truncate |
Truncates a file to a specified length |
Finally, the following methods act on the equivalent Perl variables. See Chapter 4, "The Perl Language" for more information.
Method |
Description |
---|---|
autoflush |
If nonzero, forces a flush now and after each write or print (default 0) |
format_page_number |
Current page number |
format_lines_per_page |
Current page length (default 60) |
format_lines_left |
Number of lines left on page |
format_name |
Name of current report format |
format_top_name |
Name of current top-of-page format |
format_line_break_characters |
Current set of linebreak chars for a format |
format_formfeed |
Formfeed char used by formats (default \f) |
format_write |
Wrapper for write function |
input_record_separator |
Input record separator (default newline) |
input_line_number |
Current input line number for last filehandle accessed |
output_field_separator |
Output field separator for print |
output_record_separator |
Output record separator for print |
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