about the date

bigapple · 08-01-2005, 12:03 AM

hi,all
Is there a function like get_day_of_week(), the input is a string like this:
"01-Aug-2005" and the return is the Number 1 to 7 stand for the Monday to Sunday, for example,

Code:

      int rc;
      rc = get_day_of_week("01-Aug-2005");
      switch rc
          case 1: printf("Monday!");break;
           ....
          case 7: printf("Sunday!);break;

And the input date is not the current day,may be a day some years ago.

Now I want to konw is there a function in UNIX C, if not ,how can I write this function,,how can I convert the string to be a date !

any suggest will be helpful! thx!

Matir · 08-01-2005, 12:07 AM

I guess you'd need to parse the string. Looking through the manpages for the various unix time functions, I don't find anything for string-to-date conversion, though I could just be missing it.

bigapple · 08-01-2005, 12:28 AM

you are right, I have looked up the linux c reference,and haven't seen any function for 'string-to-date', but some functions for 'date-to-string'.
The openVMS old operation system,and it has the system call "lib$day_of_week", I want to make the openVMS program run on the UNIX,So I think I must write this function myself. Do you know the openVMS is a open source system or not?

Matir · 08-01-2005, 12:37 AM

I have no idea, though the open in it sounds like it may be.

Hko · 08-01-2005, 04:09 AM

Quote:

Originally posted by bigapple
Is there a function like get_day_of_week(), the input is a string like this:
"01-Aug-2005" and the return is the Number 1 to 7 stand for the Monday to Sunday,

Have a look at man 3 strptime. I think it's almost exactly what you need.

bigapple · 08-04-2005, 10:05 PM

Thanks for Hko,
but I workstation is an AIX box,I have try 'man 3 strptime
',but it tells me the man page was not found or the strptime was not installed.
May be I will contact the Administrator of this box or try to find the source code of strptime.

eddiebaby1023 · 08-07-2005, 05:33 AM

man ctime should point you in the right direction. mktime(3) lets you create a time structure and you can then get the bit(s) you want from that.