If `.ONESHELL' is provided, then only the first line of the recipewill be checked for the special prefix characters (`@', `-', and `+').Subsequent lines will include the special characters in the recipe linewhen the `SHELL' is invoked.  If you want your recipe to start with oneof these special characters you'll need to arrange for them to not bethe first characters on the first line, perhaps by adding a comment orsimilar.  For example, this would be a syntax error in Perl because thefirst `@' is removed by make:     .ONESHELL:     SHELL = /usr/bin/perl     .SHELLFLAGS = -e     show :             @f = qw(a b c);             print "@f\n";However, either of these alternatives would work properly:     .ONESHELL:     SHELL = /usr/bin/perl     .SHELLFLAGS = -e     show :             # Make sure "@" is not the first character on the first line             @f = qw(a b c);             print "@f\n";or     .ONESHELL:     SHELL = /usr/bin/perl     .SHELLFLAGS = -e     show :             my @f = qw(a b c);             print "@f\n";   As a special feature, if `SHELL' is determined to be a POSIX-styleshell, the special prefix characters in "internal" recipe lines will_removed_ before the recipe is processed.  This feature is intended toallow existing makefiles to add the `.ONESHELL' special target andstill run properly without extensive modifications.  Since the specialprefix characters are not legal at the beginning of a line in a POSIXshell script this is not a loss in functionality.  For example, thisworks as expected:     .ONESHELL:     foo : bar/lose             @cd $(@D)             @gobble $(@F) > ../$@   Even with this special feature, however, makefiles with `.ONESHELL'will behave differently in ways that could be noticeable.  For example,normally if any line in the recipe fails, that causes the rule to failand no more recipe lines are processed.  Under `.ONESHELL' a failure ofany but the final recipe line will not be noticed by `make'.  You canmodify `.SHELLFLAGS' to add the `-e' option to the shell which willcause any failure anywhere in the command line to cause the shell tofail, but this could itself cause your recipe to behave differently.Ultimately you may need to harden your recipe lines to allow them towork with `.ONESHELL'.