Storing C Strings

[DavidWhite]

How can I store a C-string into a Fortran variable? For a string constant, I believe I can declare it as 'qwerty'C, e.g. when passing to a C routine.

To save this in a Fortran variable,would I need to use 'qwerty'//CHAR(0)?

[Jugoslav_Dujic]

Yes.

In general, you should use TRIM to ensure the text is trimmed correctly, like:

CString = TRIM(FString)//CHAR(0)

. To perform conversion other way round, use:

iLen = INDEX(CString, CHAR(0))
IF (iLen.GT.0) FString = CString(1:iLen-1)

Jugoslav

[jim_dempsey]

Jugoslav,

A few problems with the code example

CString = TRIM(FString)//CHAR(0)

Assumes CString is larger than the trimmed FString.

This would result in CString being absent of a null.

A test should be done to assure that CString is large

enough and to take appropriate action if it is not.

iLen = INDEX(CString, CHAR(0))
IF (iLen.GT.0) FString = CString(1:iLen-1)

if a Null is not in the CString FString receives no data.

Also if null string is passed (null at 1) you have a subscript error

Use:

IF (iLen.GT.1) then

  FString = CString(1:iLen-1)

else

  FString = ' '

endif

Jim Dempsey