linenum(4) Kernel Interfaces Manual linenum(4)NAME
linenum - Line number entries in an object file
DESCRIPTION
When invoked with the -g option, the cc(1) command generates an entry in the object file for each C source line on which a breakpoint is
possible. Users can then reference line numbers when debugging. (See dbx(1).)
RELATED INFORMATION a.out(4), cc(1), dbx(1), syms(4) delim off
linenum(4)
Check Out this Related Man Page
HEADERS_SENT(3) 1 HEADERS_SENT(3)headers_sent - Checks if or where headers have been sentSYNOPSIS
bool headers_sent ([string &$file], [int &$line])
DESCRIPTION
Checks if or where headers have been sent.
You can't add any more header lines using the header(3) function once the header block has already been sent. Using this function you can
at least prevent getting HTTP header related error messages. Another option is to use Output Buffering.
PARAMETERS
o $file
- If the optional $file and $line parameters are set, headers_sent(3) will put the PHP source file name and line number where out-
put started in the $file and $line variables.
o $line
- The line number where the output started.
RETURN VALUES headers_sent(3) will return FALSE if no HTTP headers have already been sent or TRUE otherwise.
EXAMPLES
Example #1
Examples using headers_sent(3)
<?php
// If no headers are sent, send one
if (!headers_sent()) {
header('Location: http://www.example.com/');
exit;
}
// An example using the optional file and line parameters, as of PHP 4.3.0
// Note that $filename and $linenum are passed in for later use.
// Do not assign them values beforehand.
if (!headers_sent($filename, $linenum)) {
header('Location: http://www.example.com/');
exit;
// You would most likely trigger an error here.
} else {
echo "Headers already sent in $filename on line $linenum
" .
"Cannot redirect, for now please click this <a " .
"href="http://www.example.com">link</a> instead
";
exit;
}
?>
NOTES
Note
Headers will only be accessible and output when a SAPI that supports them is in use.
SEE ALSO ob_start(3), trigger_error(3), headers_list(3), header(3) for a more detailed discussion of the matters involved. .
PHP Documentation Group HEADERS_SENT(3)