%SUCCESS
Determine if low-order bit is on or off
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VSupported on OpenVMS
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status = %SUCCESS(expression)
Return value
status
0 if the low-order bit of expression is off, or 1 if the low-order bit is on. (i)
Arguments
expression
Any valid numeric expression. (n)
Discussion.
We recommend using a .BAND. test of bit 1 rather than %SUCCESS. |
Examples
This example function calls an OpenVMS system function to determine whether or not a file exists. It calls %SUCCESS to check the status of the return value from this system function.
function file_exists external function lib$find_file ,^val ;OpenVMS system function record context ,i4 ;Arguments for lib$find_file return_file_spec ,i4 ffile ,i4 ;For the return value proc context = 0 ffile = %lib$find_file(filename, return_file_spec, ^ref(context),,,,) xcall lib%find_file_end(^ref(context)) ; Release context block if (%success(ffile)) then freturn (%true) ;File exists else freturn (%false) ;File doesn't exist endfunction