apenwarr-redo/t/example/CC.do

redo-ifchange config.sh
. ./config.sh
exec >$3
cat <<-EOF
	redo-ifchange \$1.c
	gcc $CFLAGS -MD -MF \$3.deps -o \$3 -c \$1.c
	read DEPS <\$3.deps
	rm -f \$3.deps
	redo-ifchange \${DEPS#*:}
EOF
chmod +x $3
Add t/example, a basic example build environment suitable for a tutorial. 2010-11-17 19:49:41 -08:00			`redo-ifchange config.sh`
			`. ./config.sh`
$3 and stdout no longer refer to the same file. This is slightly inelegant, as the old style echo foo echo blah chmod a+x $3 doesn't work anymore; the stuff you wrote to stdout didn't end up in $3. You can rewrite it as: exec >$3 echo foo echo blah chmod a+x $3 Anyway, it's better this way, because now we can tell the difference between a zero-length $3 and a nonexistent one. A .do script can thus produce either one and we'll either delete the target or move the empty $3 to replace it, whichever is right. As a bonus, this simplifies our detection of whether you did something weird with overlapping changes to stdout and $3. 2010-12-11 00:29:04 -08:00			`exec >$3`
Add t/example, a basic example build environment suitable for a tutorial. 2010-11-17 19:49:41 -08:00			`cat <<-EOF`
			`redo-ifchange \$1.c`
Simplify autodependency examples. Turns out we don't need sed to process the output of gcc -MD. We can just do this: read DEPS <filename.deps The 'read' command in sh actually handles backslashes correctly, so we don't have to sed them out after all. And then a simple ${DEPS#*:} removes the "target:" prefix from the dependency line, and we're done! 2011-02-21 03:57:48 -08:00			`gcc $CFLAGS -MD -MF \$3.deps -o \$3 -c \$1.c`
			`read DEPS <\$3.deps`
			`rm -f \$3.deps`
			`redo-ifchange \${DEPS#*:}`
Add t/example, a basic example build environment suitable for a tutorial. 2010-11-17 19:49:41 -08:00			`EOF`
			`chmod +x $3`