doc: Clarify name of files generated by pg_waldump --save-fullpage

The fork name is always separated with the block number by an underscore
in the names of the files generated, but the docs stuck them together
without a separator, which was confusing.

Author: Christoph Berg
Discussion: https://postgr.es/m/[email protected]
Backpatch-through: 16

diff --git a/doc/src/sgml/ref/pg_waldump.sgml b/doc/src/sgml/ref/pg_waldump.sgml
index a9371e037bde56b2fa7f2350a68077c535007404..ce23add5577ed2ccedf111f3b427fafeb8ad9cd6 100644 (file)
--- a/doc/src/sgml/ref/pg_waldump.sgml
+++ b/doc/src/sgml/ref/pg_waldump.sgml
@@ -284,7 +284,7 @@ PostgreSQL documentation
        
        
         The full page images are saved with the following file name format:
-        TIMELINE-LSN.RELTABLESPACE.DATOID.RELNODE.BLKNOFORK
+        TIMELINE-LSN.RELTABLESPACE.DATOID.RELNODE.BLKNO_FORK
 
         The file names are composed of the following parts:
         
@@ -335,8 +335,8 @@ PostgreSQL documentation
             FORK
             
              The name of the fork the full page image came from, such as
-             _main, _fsm,
-             _vm, or _init.
+             main, fsm,
+             vm, or init.