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how to write a C program which has the function of "Who"?

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# 1  
Old 10-09-2003
how to write a C program which has the function of "Who"?
how to write a C program which has the function of "Who"?
how to read the user informations---the data structures stored in /var/adm/utmpx and display them?

somebody plz help!!!
# 2  
Old 10-10-2003
this seems like homework, is it? see rule six please:

(6) Do not post classroom or homework problems.

you can name functions in C whatever you want. if you want a function called 'Who' then name it 'Who'. C programs will generally have more than one function, and always have at least one function, always called 'main()'.


see the man pages for 'utmp', take a look at the 'see also: ...' at the bottom.
# 3  
Old 10-10-2003
You're taking him too literally, norsk. He doesn't literally mean a function named who. He want to duplicate the who program.

Also, this would not a very poor choice for a homework assignment. That would be especially true at this point in time. The format of the utmp file is evolving right now. A portable answer to this question really is not possible. A portable who program would need a ton of ifdefs.

Your file may be named utmp or utmpx or both. You will want the x version if you have it.

Five years ago I could have told you to just call getutmp() in a loop, select the interesting records, and print them out. Now you may have getutmpx(), if so, use that. Both will be mentioned in "man getutmp" if that exists. Or you may just have a "man getutmpx".

But in any event, just call whichever in a loop, select the interesting records, and display them.
# 4  
Old 10-10-2003
ohhhh i get it... 'function' as in works like...my fault. Smilie
# 5  
Old 10-10-2003
I see that I fumbled too. I shouldn't post until I wakeup. I meant to say this "would be a poor choice for a homework assignment".
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