что означает @@ в патчах

patch -p0 << EOF --- old/modules/pcitable Mon Sep 27 11:03:56 1999 +++ new/modules/pcitable Tue Dec 19 20:05:41 2000 @@ -1,4 +1,6 @@ 0x0e11 0xae10 "cpqarray" "Compaq|Smart-2/P RAID Controller" +0x1000 0x0010 "cpqarray" "Compaq|Integrated Array Controller" +0x1011 0x0046 "cpqarray" "Compaq|Smart-2/P RAID Controller" 0x0e11 0xae32 "tlan" "Compaq|Netelligent 10/100" 0x0e11 0xae34 "tlan" "Compaq|Netelligent 10" 0x0e11 0xae35 "tlan" "Compaq|Integrated NetFlex-3/P" @@ -21,6 +23,7 @@ 0x1000 0x000f "ncr53c8xx" "Symbios|53c875"