not cache imagepng() ?

[leeming]

i have this picture that is made using the imagepng() function.. but im having a few users report to me that they are seeing an outdated version of the picture (and im guessing its cos its been cache on their machine).. is there any way i can made it so this doesnt happen?

[Barand]

Are you using imagepng($im, $filename) to write the the image to a file then displaying the resultant file

<img src='filename.png'>

or are you displaying the dynamic image

<img src='myimage.php'>

I was under the impression that if it's the latter it cannot be cached as the image file doesn't exist until it is created on-the-fly.

[leeming]

[quote author=Barand link=topic=112131.msg455136#msg455136 date=1161372394]
Are you using imagepng($im, $filename) to write the the image to a file then displaying the resultant file

<img src='filename.png'>

or are you displaying the dynamic image

<img src='myimage.php'>

I was under the impression that if it's the latter it cannot be cached as the image file doesn't exist until it is created on-the-fly.
[/quote]
its shown as a .png, because it saves load time every time a page is viewed... and the picture is only updated as updates happen

[dark dude]

Not sure if this might work, but have you tried using the <META HTTP-EQUIV="PRAGMA" CONTENT="NO-CACHE"> html tag?