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# Porting alien software *without* APE

To get started on an easy port of a POSIX library (or a program), one
can use
[helpmeport](https://git.sr.ht/~ft/snippets/blob/master/helpmeport)
script.  It tries to generate the appopriate headers and a `mkfile`.

	cd coollib
	# sometimes, the source files are located in `src` subdir
	# if it's in the current directory, just specify `.` instead
	rm -rf mkfile src/plan9 # remove old stuff
	helpmeport src | rc
	# now there is `src/plan9` directory and `mkfile`
	# `mkfile` needs manual adjustments: open it and search for "FIXME"
	# make your choices (name of the library/program, etc)
	# clean up headers and sources, some of them might be platform-specific
	B mkfile
	# now try to build. there is 99% it won't work the first time
	mk

Depending on the result of the build, some changes of the source code
might be required.

The script will provide `__plan9__` and eg `__amd64__` definitions to
be used throughout, in case needed.

Feel free to show your script patches and ideas to Sigrid.

## Common issues

### function not declared: ...

If the function defined in the project, and has no arguments, make
sure it's declared as `(void)` instead of `()`.

### alloca

`alloca` allocates memory on stack, so that freeing it isn't required.
Plan 9 does not have that.  It has to be replaced with `malloc` and
`free` call before leaving the function.

### *_MAX or *_MIN not declared

Grep `/sys/include` to see if it's already defined in APE:

	g UCHAR_MAX /sys/include/ape

In most of the cases you can just add it to `src/plan9/plan9.h`.  Be
careful if the size depends on the CPU you're targetting.