Paul Eggert wrote:
> PS. There's a lot of machinery in those shell scripts for the minor
> benefit of letting gnulib-tool be a symlink in your $PATH to the real
> gnulib-tool. How about if we drop support for this?
This is not a "minor" benefit, but a major one.
1) It's documented:
<https://www.gnu.org/software/gnulib/manual/html_node/Invoking-gnulib_002dtool.html>
2) If it was not present, the user would have to write a shell-script wrapper;
however, some users are not proficient enough with shell scripting ('exec',
"$@", etc.) to be able to write such a wrapper.
3) The GNU Coding Standards
<https://www.gnu.org/prep/standards/html_node/Finding-Program-Files.html>
also say that programs should handle this case:
"If the invocation directory doesn’t contain what’s needed, but
the executable file name is a symbolic link, the program should
try using the link target’s containing directory as the invocation
directory."
On POSIX systems, users are supposed to be able to use symlinks for data
files - with no need to write a Hurd translator. And likewise, users are
supposed to be able to use symlinks for programs - with no need to write
a shell script wrapper.
> That'd simplify startup quite a bit
It is sad that POSIX did not specify some shell built-ins (other than "$0")
that would make this task easy for shell scripts. (OK, they have added the
'readlink' program now in 2024. It's at least a start.) But it's the way it is,
and our solution is perfectly copy-and-pastable from one program to another.
I therefore vehemently disagree with your suggestion and patch.
> PPS. Why do we have both gnulib-tool.py and .gnulib-tool.py? Is this
> commented in the source code?
Yes, there is a large comment about it in .gnulib-tool.py.
And why gnulib-tool.py is a shell script, not a Python script, is obvious
from what it contains:
- It needs to find the invocation directory.
- It needs to set environment variables for Python.
- It may need to add command-line arguments for Python.
- It provides a decent error message if Python is not found or too old.
Bruno
