FIND_WITH_DEF
Name
FIND_WITH_DEF()
Purpose
Searches for files with a default path and extension.
Explanation
Finds files using default paths and extensions, Using this routine
together with environment variables allows an OS-independent approach
to finding files.
Calling Sequence
Result = FIND_WITH_DEF( FILENAME, PATHS [, EXTENSIONS ] )
Inputs
FILENAME = Name of file to be searched for. It may either be a
complete filename, or the path or extension could be left
off, in which case the routine will attempt to find the
file using the default paths and extensions.
PATHS = One or more default paths to use in the search in case
FILENAME does not contain a path itself. The individual
paths are separated by commas, although in UNIX, colons
can also be used. In other words, PATHS has the same
format as !PATH, except that commas can be used as a
separator regardless of operating system. The current
directory is always searched first, unless the keyword
NOCURRENT is set.
A leading $ can be used in any path to signal that what
follows is an environmental variable, but the $ is not
necessary. Environmental variables can themselves contain
multiple paths.
Optional Inputs
EXTENSIONS = Scalar string giving one or more extensions to append to
end of filename if the filename does not contain one (e.g.
".dat"). The period is optional. Multiple extensions can
be separated by commas or colons.
Outputs
The result of the function is the name of the file if successful, or
the null string if unsuccessful.
Optional Input Keywords
NOCURRENT = If set, then the current directory is not searched.
RESET = The FIND_WITH_DEF routine supports paths which are
preceeded with the plus sign to signal that all
subdirectories should also be searched. Often this is
used with logical names. It can be rather slow to search
through these subdirectories. The /RESET keyword can be
used to redefine an environment variable so that
subsequent calls don't need to look for the
subdirectories.
To use /RESET, the PATHS parameter must contain the name
of a *single* environment variable. For example
setenv,'FITS_DATA=+/datadisk/fits'
file = find_with_def('test.fits','FITS_DATA',/reset)
Example
FILENAME = ''
READ, 'File to open: ', FILENAME
FILE = FIND_WITH_DEF( FILENAME, 'SERTS_DATA', '.fix' )
IF FILE NE '' THEN ...
Procedure Calls
BREAK_PATH(), FIND_ALL_DIR(), STR_SEP()
Revision History
Version 1, William Thompson, GSFC, 3 May 1993.
Removed trailing / and : characters.
Fixed bugs
Allow for commas within values of logical names.
Added keyword NOCURRENT.
Changed to call BREAK_PATH
Version 2, William Thompson, GSFC, 3 November 1994
Made EXTENSIONS optional.
Version 3, William Thompson, GSFC, 30 April 1996
Call FIND_ALL_DIR to resolve any plus signs.
Version 4, S.V. Haugan, UiO, 5 June 1996
Using OPENR,..,ERROR=ERROR to avoid an IDL 3.6
internal nesting error.
Version 5, R.A. Schwartz, GSFC, 11 July 1996
Use SPEC_DIR to interpret PATH under VMS
Version 6, William Thompson, GSFC, 5 August 1996
Took out call to SPEC_DIR (i.e., reverted to version 4). The
use of SPEC_DIR was required to support logical names defined
via SETLOG,/CONFINE. However, it conflicted with the ability
to use logical names with multiple values. Removing the
/CONFINE made it unnecessary to call SPEC_DIR in this routine.
Version 7, William Thompson, GSFC, 6 August 1996
Added keyword RESET
Converted to IDL V5.0 W. Landsman October 1997
Use STRTRIM instead of TRIM, W. Landsman November 1998
Use STRSPLIT instead of STR_SEP W. Landsman July 2002