Replace si::*command-args* by the the list starting after -f.
Open the file following -f for input, skip the first line, and then
read and eval the rest of the forms in the file. This can be used
as with the shells to write small shell programs:
| | #!/usr/local/bin/gcl.exe -f
(format t "hello world ~a~%" (nth 1 si::*command-args*))
|
The value si::*command-args* will have the appropriate value.
Thus if the above 2 line file is made executable and called `foo'
then
| | tutorial% foo billy
hello world billy
|
NOTE: On many systems (eg SunOs) the first line of an executable script file
such as:
| | #!/usr/local/bin/gcl.exe -f
|
only reads the first 32 characters! So if your pathname where the executable
together with the '-f' amount to more than 32 characters the file will not
be recognized. Also the executable must be the actual large binary file,
[or a link to it],
and not just a /bin/sh script. In latter case the
/bin/sh interpreter would get invoked on the file.
Alternately one could invoke the file `foo' without making it
executable:
| | tutorial% gcl -f foo "from bill"
hello world from bill
|
Finally perhaps the best way (why do we save the best for last..
I guess because we only figure it out after all the others..)
The following file `myhello' has 4 lines:
| | #!/bin/sh
#| Lisp will skip the next 2 lines on reading
exec gcl -f "$0" $
|#
(format t "hello world ~a~%" (nth 1 si::*command-args*))
|
| | marie% chmod a+x myhello
marie% myhello bill
hello world bill
|
The advantage of this method is that `gcl' can itself
be a shell script, which sets up environment and
so on. Also the normal path will be searched to find `gcl'
The disadvantage is that this would cause 2 invocations of `sh'
and one invocation of `gcl'. The plan using `gcl.exe'
bypasses the `sh' entirely. Inded invoking `gcl.exe' to
print `hello world' is faster on most systems than a similar
`csh' or `bash' script, but slightly slower than the old
`sh'.
