Title: Calling function from other plugins
Last modified: August 20, 2016

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# Calling function from other plugins

 *  [Kendall Arneaud](https://wordpress.org/support/users/icecappacino/)
 * (@icecappacino)
 * [13 years, 4 months ago](https://wordpress.org/support/topic/calling-function-from-other-plugins/)
 * I’m trying to call a plugin’s function in my themes’ function file but I get 
   an error stating that the function is undefined.
 * How can I know when a plugin is loaded so as to call the function as well as 
   call the function before outputting headers?

Viewing 4 replies - 1 through 4 (of 4 total)

 *  [michael.mariart](https://wordpress.org/support/users/michaelmariart/)
 * (@michaelmariart)
 * [13 years, 4 months ago](https://wordpress.org/support/topic/calling-function-from-other-plugins/#post-3236473)
 * You can try:
 *     ```
       if (function_exists("other_function_name")){
           // Do your stuff in here
       }
       ```
   
 *  Thread Starter [Kendall Arneaud](https://wordpress.org/support/users/icecappacino/)
 * (@icecappacino)
 * [13 years, 4 months ago](https://wordpress.org/support/topic/calling-function-from-other-plugins/#post-3236483)
 * Yes but that doesn’t help me it just checks to see if the function exists….i 
   need it to exists…i need to know when a particular plugin is loaded
 *  [dsomaya](https://wordpress.org/support/users/dsomaya/)
 * (@dsomaya)
 * [13 years, 4 months ago](https://wordpress.org/support/topic/calling-function-from-other-plugins/#post-3236484)
 * there is a solution given in the forum. you can check this link. [http://wordpress.org/support/topic/how-to-check-if-another-plugin-is-active?replies=7](http://wordpress.org/support/topic/how-to-check-if-another-plugin-is-active?replies=7)
 *  Thread Starter [Kendall Arneaud](https://wordpress.org/support/users/icecappacino/)
 * (@icecappacino)
 * [13 years, 4 months ago](https://wordpress.org/support/topic/calling-function-from-other-plugins/#post-3236489)
 * Well that is going to suck I’m trying to do [this >>](http://wordpress.org/support/topic/how-to-use-facebook-user-as-wordpress-user?replies=1)
 * _[ Duplicate [http://wordpress.org/support/topic/how-to-use-facebook-user-as-wordpress-user?replies=1](http://wordpress.org/support/topic/how-to-use-facebook-user-as-wordpress-user?replies=1)–
   Closing. Don’t create multiple threads for the same thing it makes support more
   difficult. Continue on with the other post. ]_

Viewing 4 replies - 1 through 4 (of 4 total)

The topic ‘Calling function from other plugins’ is closed to new replies.

## Tags

 * [custom](https://wordpress.org/support/topic-tag/custom/)
 * [init](https://wordpress.org/support/topic-tag/init/)

 * 4 replies
 * 3 participants
 * Last reply from: [Kendall Arneaud](https://wordpress.org/support/users/icecappacino/)
 * Last activity: [13 years, 4 months ago](https://wordpress.org/support/topic/calling-function-from-other-plugins/#post-3236489)
 * Status: not resolved

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