Processing argv

Processing argv

[Buddy Lumpkin]

Ok so the announcement for release 0.7 says the following:

 - The vector of script command line arguments is available in a
   tapset-provided global array argv[].  It is indexed 1 ... argc,
   another global.  This can substitute for of preprocessor
   directives @NNN that fail at parse time if there are not
   enough arguments.
       printf("argv: %s %s %s", argv[1], argv[2], argv[3])

 For a full overview see the SystemTap Language Reference manual.

I cannot find an updated reference manual that gives a full overview.
This manual does not seem to cover it:
http://sourceware.org/systemtap/langref/

There doesn't seem to be a built in atoi. Is there an sscanf or an
intended method for converting strings to ints or do I need to roll my
own?

--Buddy

Re: Processing argv

[Buddy Lumpkin]

Also, can staprun process command line arguments? My testing seems to
indicate that it can't but perhaps I am not quoting or escaping things
correctly?

--Buddy

On Thu, Jan 8, 2009 at 2:06 PM, Buddy Lumpkin <buddy.lumpkin@gmail.com> wrote:
> Ok so the announcement for release 0.7 says the following:
>
>  - The vector of script command line arguments is available in a
>   tapset-provided global array argv[].  It is indexed 1 ... argc,
>   another global.  This can substitute for of preprocessor
>   directives @NNN that fail at parse time if there are not
>   enough arguments.
>       printf("argv: %s %s %s", argv[1], argv[2], argv[3])
>
>  For a full overview see the SystemTap Language Reference manual.
>
> I cannot find an updated reference manual that gives a full overview.
> This manual does not seem to cover it:
> http://sourceware.org/systemtap/langref/
>
> There doesn't seem to be a built in atoi. Is there an sscanf or an
> intended method for converting strings to ints or do I need to roll my
> own?
>
> --Buddy
>

Re: Processing argv

[Mark Wielaard]

Hi Buddy,

On Thu, 2009-01-08 at 14:06 -0800, Buddy Lumpkin wrote:
> Ok so the announcement for release 0.7 says the following:
> 
>  - The vector of script command line arguments is available in a
>    tapset-provided global array argv[].  It is indexed 1 ... argc,
>    another global.  This can substitute for of preprocessor
>    directives @NNN that fail at parse time if there are not
>    enough arguments.
>        printf("argv: %s %s %s", argv[1], argv[2], argv[3])
> 
>  For a full overview see the SystemTap Language Reference manual.
> 
> I cannot find an updated reference manual that gives a full overview.
> This manual does not seem to cover it:
> http://sourceware.org/systemtap/langref/

Seems you are right. It is actually only documented in the manual page
for stapvars (5). BTW. the language reference manual should also be
installed locally, probably somewhere as:
/usr/share/doc/systemtap-0.8/langref.pdf
(but indeed, the new argv/argc support isn't in there, sorry)

> There doesn't seem to be a built in atoi. Is there an sscanf or an
> intended method for converting strings to ints or do I need to roll my
> own?

There is strtol:long (str:string, base:long)
That one is documented in the language reference (9.9 String Functions)

Cheers,

Mark

Re: Processing argv

[Mark Wielaard]

On Thu, 2009-01-08 at 14:57 -0800, Buddy Lumpkin wrote:
> Also, can staprun process command line arguments? My testing seems to
> indicate that it can't but perhaps I am not quoting or escaping things
> correctly?

Do you mean with -c?
Then yes, if you quote the whole argument to -c it should act like it is
all passed to sh -c "your arguments". There were some issues with this
in the past though, see for example
https://bugzilla.redhat.com/show_bug.cgi?id=467652

Cheers,

Mark