The Intel® Fortran run-time system recognizes a number of environment variables. These variables can be used to customize run-time diagnostic error reporting, allow program continuation under certain conditions, disable the display of certain dialog boxes under certain conditions, and allow just-in-time debugging. For a list of run-time environment variables used by OpenMP*, see OpenMP Environment Variables in Optimizing Applications.
For information on setting compile time environment variables, see Setting Compile-Time Environment Variables.
The run-time environment variables are:
decfort_dump_flag
If this variable is set to Y or y, a core dump will be taken when any severe Intel Fortran run-time error occurs.
F_UFMTENDIAN
This variable specifies the numbers of the units to be used for little-endian-to-big-endian conversion purposes. See Environment Variable F_UFMTENDIAN Method.
FOR_FMT_TERMINATOR
This variable specifies the numbers of the units to have a specific record terminator. See Record Types.
FOR_ACCEPT
The ACCEPT statement does not include an explicit logical unit number. Instead, it uses an implicit internal logical unit number and the FOR_ACCEPT environment variable. If FOR_ACCEPT is not defined, the code ACCEPT f,iolist
reads from CONIN$ (standard input). If FOR_ACCEPT is defined (as a file name optionally containing a path), the specified file would be read.
FOR_DEBUGGER_IS_PRESENT
This variable tells the Fortran run-time library that your program is executing under a debugger. If set to True, it generates debug exceptions whenever severe or continuous errors are detected. Under normal conditions you don't need to set this variable on Windows systems, as this information can be extracted from the operating system. On Linux* OS and Mac OS* X, you will need to set this variable if you want debug exceptions. Setting this variable to True when your program is not executing under a debugger will cause unpredictable behavior.
FOR_DEFAULT_PRINT_DEVICE (Windows* OS only)
This variable lets you specify the print device other than the default print device PRN (LPT1) for files closed (CLOSE statement) with the DISPOSE='PRINT' specifier. To specify a different print device for the file associated with the CLOSE statement DISPOSE='PRINT' specifier, set FOR_DEFAULT_PRINT_DEVICE to any legal DOS print device before executing the program.
FOR_DIAGNOSTIC_LOG_FILE
If this variable is set to the name of a file, diagnostic output is written to the specified file.
The Fortran run-time system attempts to open that file (append output) and write the error information (ASCII text) to the file.
The setting of FOR_DIAGNOSTIC_LOG_FILE is independent of FOR_DISABLE_DIAGNOSTIC_DISPLAY, so you can disable the screen display of information but still capture the error information in a file. The text string you assign for the file name is used literally, so you must specify the full name. If the file open fails, no error is reported and the run-time system continues diagnostic processing.
See also Locating Run-Time Errors and Using Traceback Information.
FOR_DISABLE_DIAGNOSTIC_DISPLAY
This variable disables the display of all error information. This variable is helpful if you just want to test the error status of your program and do not want the Fortran run-time system to display any information about an abnormal program termination.
See also Using Traceback Information.
FOR_DISABLE_STACK_TRACE
This variable disables the call stack trace information that follows the displayed severe error message text.
The Fortran run-time error message is displayed whether or not FOR_DISABLE_STACK_TRACE is set to true. If the program is executing under a debugger, the automatic output of the stack trace information by the Fortran library will be disabled to reduce noise. You should use the debugger's stack trace facility if you want to view the stack trace.
See also Locating Run-Time Errors and Using Traceback Information.
FOR_IGNORE_EXCEPTIONS
This variable disables the default run-time exception handling, for example, to allow just-in-time debugging. The run-time system exception handler returns EXCEPTION_CONTINUE_SEARCH to the operating system, which looks for other handlers to service the exception.
FOR_NOERROR_DIALOGS
This variable disables the display of dialog boxes when certain exceptions or errors occur. This is useful when running many test programs in batch mode to prevent a failure from stopping execution of the entire test stream.
FOR_PRINT
Neither the PRINT statement nor a WRITE statement with an asterisk (*) in place of a unit number includes an explicit logical unit number. Instead, both use an implicit internal logical unit number and the FOR_PRINT environment variable. If FOR_PRINT is not defined, the code PRINT f,iolist
or WRITE (*,f) iolist
writes to CONOUT$ (standard output). If FOR_PRINT is defined (as a file name optionally containing a path), the specified file would be written to.
FOR_READ
A READ statement that uses an asterisk (*) in place of a unit number does not include an explicit logical unit number. Instead, it uses an implicit internal logical unit number and the FOR_READ environment variable. If FOR_READ is not defined, the code READ (*,f) iolist
or READ f,iolist
reads from CONIN$ (standard input). If FOR_READ is defined (as a file name optionally containing a path), the specified file would be read.
FOR_TYPE
The TYPE statement does not include an explicit logical unit number. Instead, it uses an implicit internal logical unit number and the FOR_TYPE environment variable. If FOR_TYPE is not defined, the code TYPE f,iolist
writes to CONOUT$ (standard output). If FOR_TYPE is defined (as a file name optionally containing a path), the specified file would be written to.
FORT_BUFFERED
Lets you request that buffered I/O should be used at run time for output of all Fortran I/O units, except those with output to the terminal. This provides a run-time mechanism to support the -assume buffered_io (Linux OS and Mac OS X) or /assume:buffered_io (Windows OS) compiler option.
FORT_FMT_RECL
Lets you specify the default record length (normally 132 bytes) for formatted files.
FORT_UFMT_RECL
Lets you specify the default record length (normally 2040 bytes) for unformatted files.
FORTn
Lets you specify the file name for a particular unit number n, when a file name is not specified in the OPEN statement or an implicit OPEN is used, and the compiler option -fpscomp filesfromcmd (Linux OS and Mac OS X) or /fpscomp:filesfromcmd (Windows OS) was not specified. Preconnected files attached to units 0, 5, and 6 are by default associated with system standard I/O files.
TBK_FULL_SRC_FILE_SPEC
By default, the traceback output displays only the file name and extension in the source file field. To display complete file name information including the path, set the environment variable TBK_FULL_SRC_FILE_SPEC to true.
The variable FOR_FULL_SRC_FILE_SPEC is also recognized for compatibility with Compaq* Visual Fortran.
See also Using Traceback Information.
You can set a run-time environment variable from within a program by calling the SETENVQQ routine. For example:
program ENVVAR
use ifport
LOGICAL(4) res
! Add other data declarations here
! call SETENVQQ as a function
res=SETENVQQ("FOR_IGNORE_EXCEPTIONS=T")