get_trackback_url(): string
- Since
- 1.5.0
- Source
wp-includes/comment-template.php:1221
Description
There is a check to see if permalink's have been enabled and if so, will retrieve the pretty path. If permalinks weren't enabled, the ID of the current post is used and appended to the correct page to go to.
Compatibility
- WordPress
- since 1.5.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Return value
string- The trackback URL after being filtered.
Performance profile
How much work a call to get_trackback_url() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Heavy
- Scaling
- Constant
- Instructions
- 16–20
- Plugin surface
- 1 hook
- Called by
- 2
Reaches the database via get_post().
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 27.
Third-party callbacks on 'trackback_url' run inside this call, and their cost is not bounded by anything here.
2 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- optionoption read or write
get_option()called directly - hookthird-party callbacks
apply_filters()called directly - cacheobject cache
wp_cache_get()one call below get_trackback_url() - serializeserialisation
maybe_unserialize()one call below get_trackback_url() - querycontent query
get_post()one call below get_trackback_url()
Further down the call graph this can also reach transient. That is the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost get_trackback_url() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
!get_option() | 16 | get_option(), get_option(), get_the_ID(), apply_filters() |
get_option() | 20 | get_option(), get_permalink(), trailingslashit(), user_trailingslashit(), apply_filters() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 27 instructions, 16–20 executed per call, 1 branch. The work does not change between versions.
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Hooks and filters fired · 1
One hook fires while get_trackback_url() runs, in this order:
- apply_filters( trackback_url )filterline 1235 (+14 into the body)
Filters the returned trackback URL.
Uses · 6
- get_option()Retrieves an option value based on an option name.
- trailingslashit()Appends a trailing slash.
- get_permalink()Retrieves the full permalink for the current post or post ID.
- user_trailingslashit()Retrieves a trailing-slashed string if the site is set for adding trailing slashes.
- get_the_ID()Retrieves the ID of the current item in the WordPress Loop.
- apply_filters()Calls the callback functions that have been added to a filter hook.
Used by · 2
- trackback_rdf()Generates and displays the RDF for the trackback information of current post.
- trackback_url()Displays the current post's trackback URL.
Source code
function get_trackback_url() { if ( get_option( 'permalink_structure' ) ) { $trackback_url = trailingslashit( get_permalink() ) . user_trailingslashit( 'trackback', 'single_trackback' ); } else { $trackback_url = get_option( 'siteurl' ) . '/wp-trackback.php?p=' . get_the_ID(); } /** * Filters the returned trackback URL. * * @since 2.2.0 * * @param string $trackback_url The trackback URL. */ return apply_filters( 'trackback_url', $trackback_url );}Changelog
Introduced in 1.5.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 7.0.4 tag, from
src/wp-includes/comment-template.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.