It looks like the cron does not have
$BPY defined. Is it
some_script.py that needs to be executed? What's the purpose of
$BPY? Also, you should probably need the full path of the script, not just the script's name itself.
some_script.py is the real intended executed script, then try just executing that (with the full path!!)
In your comments below this answer, you said the
$BPY is Python's path. Instead of doing that, you should use a
shebang to specify the full path of the interpreter that is to be used. A common shebang specifying python is:
#!/usr/bin/python. This should be the first line of your
As far as the syntax...
Cron format is a simple, yet powerful and flexible way to define time and frequency of various actions.
cron format consists of fields separated by white spaces:
[Min] [Hr] [Day of Month] [Month of Year] [Day of Week]
The following diagram shows what it consists of:
* * * * *
| | | | |
| | | | +---- Day of the Week (range: 0-6, 0 standing for Sunday; Mon,Tue, etc.
| | | | Most OS's recognize Sunday as 0 or 7)
| | | +------ Month of the Year (range: 1-12 or Jan, Feb, etc)
| | +-------- Day of the Month (range: 1-31)
| +---------- Hour (range: 0-23)
+------------ Minute (range: 0-59)
Any of these 6 fields may be an asterisk (
*). This would mean the entire range of possible values, i.e. each minute, each hour, etc. In the first four fields.
Any field may contain a list of values separated by commas, (e.g.
1,3,7) or a range of values (two integers separated by a hyphen, e.g.
After an asterisk (
*) or a range of values, you can use character
/ to specify that values are repeated over and over with a certain interval between them. For example, you can write
0-23/2 in the Hour field to specify that some action should be performed every two hours (it will have the same effect as
0,2,4,6,8,10,12,14,16,18,20,22). A value of
*/4 in the Minute field means that the action should be performed every 4 minutes.
1-30/3 means the same as
In Month and Day of Week fields, you can use names of months or days of weeks abbreviated to first three letters (
Sun) instead of their numeric values.
Alternatively, you can use special keywords in lieu of the first 5 fields specified above:
@reboot Run once, at startup.
@yearly Run once a year, "0 0 1 1 *".
@annually (same as @yearly)
@monthly Run once a month, "0 0 1 * *".
@weekly Run once a week, "0 0 * * 0".
@daily Run once a day, "0 0 * * *".
@midnight (same as @daily)
@hourly Run once an hour, "0 * * * *".
This alternate format is not supported in older, proprietary operating systems like SCO Unix.