Search code examples
ubuntumakefilegnu-makerecipe

What is the leading "@" at the recipe of a makefile


In a makefile that is generated by eclipse, I see the following rules:

./Cores/$(TARGET).core.3.srec : ../$(TARGET).core.3/Debug/$(TARGET).core.3.elf
        @mkdir -p ./Cores/
        @e-objcopy --srec-forceS3 --output-target srec "$<" "$@".temp
        @echo Creating srec file for CoreID\<0x826\>
        @head --lines=1 "$@".temp  | sed 's/0000/0826/' > "$@"
        @tail --lines=+2 "$@".temp >> "$@"

What is the purpose of the "@" at the beginning of the recipe lines?

Reading through the GNU Make user's manual I could not find a reference to this use of @. I then assumed that it is actually transferred as-is to the shell.

So, reading the BASH manual, the only place I could relate to this use is in command substitution when the extglob option is set. However, trying this in the command line gave me an error.


Solution

  • The @ prefix causes make to run the command silently. See this section of the GNU make manual.