FILENAME Statement: UNIX

fileref

is the name by which you reference the file. Under UNIX, the value of fileref can be an environment variable.

Note:   You cannot clear a fileref that is defined by an environment variable. Filerefs that are defined by an environment variable are assigned for the entire SAS session.  

See Using Environment Variables to Assign Filerefs in UNIX Environments for more information.

device-type

specifies a device for the output, such as a disk, terminal, printer, pipe, and so on. The device-type keyword must follow fileref and precede pathname. Device Information in the FILENAME Statement describes the valid device types. DISK is the default device type. If you are associating the fileref with a DISK file, then you do not need to specify the device type.

'external-file'

differs according to device type. Device Information in the FILENAME Statement shows the information appropriate to each device. Remember that UNIX filenames are case sensitive. See Specifying Pathnames in UNIX Environments for more information.

Note:   If a filename has leading blanks, then they will be trimmed.  

ENCODING='encoding-value'

specifies the encoding to use when reading from or writing to the external file. The value for ENCODING= indicates that the external file has a different encoding from the current session encoding.

When you read data from an external file, SAS transcodes the data from the specified encoding to the session encoding. When you write data to an external file, SAS transcodes the data from the session encoding to the specified encoding.

For valid encoding values, see Encoding Values in SAS Language Elements in the SAS National Language Support (NLS): Reference Guide.

'host-options'

are specific to UNIX environments. These options can be any of the following:

BLKSIZE=
BLK=

specifies the number of bytes that are physically written or read in one I/O operation. The default is 8K. The maximum is 1G-1. If you specify RECFM=S370VBS, then you should specify BLKSIZE=32760 in order to avoid errors with records longer than 255 characters.

TERMSTR=

controls the end of line/record delimiters in PC and UNIX formatted files. This option enables the sharing of UNIX and PC formatted files between the two hosts. The following values for the TERMSTR= option are valid:

CRLF	Carriage Return Line Feed. This parameter is used to read and write PC format files.
NL	Newline. This parameter is used to read and write UNIX format files. NL is the default format.

If you are working on UNIX and reading a file that was created on a PC, specify TERMSTR=CRLF unless the file was created with the TERMSTR=NL option. If you are writing a file that will be read on a PC, specify TERMSTR=CRLF.

If you are working on a PC and reading a file that was created on UNIX, specify TERMSTR=NL unless the file was created with the TERMSTR=CRLF option. If you are writing a file that will be read on UNIX, specify TERMSTR=NL.

LRECL=

specifies the logical record length. Its meaning depends on the record format in effect (RECFM). The default is 256. The maximum length is 1G.

• If RECFM=F, then the value for the LRECL= option determines either the number of bytes to be read as one record or the length of each output record. The output record is truncated or padded with blanks to fit the specified size.

• If RECFM=N, then the value for the LRECL= option must be at least 256.

• If RECFM=V, then the value for the LRECL= option determines the maximum record length. Records that are longer than the specified length are divided into multiple records on output and truncated on input.

• If RECFM=S370VBS, then you should specify LRECL=32760 in order to avoid errors with records longer than 255 characters.

MOD

indicates that data written to the file should be appended to the file.

NEW | OLD

indicates that a new file is to be opened for output. If the file already exists, then it is deleted and re-created. If you specify OLD, then the previous contents of the file are replaced. NEW is the default.

RECFM=

specifies the record format. Values for the RECFM= option are the following:

D	default format (same as variable).
F	fixed format. That is, each record has the same length. Do not use RECFM=F for external files that contain carriage-control characters.
N	binary format. The file consists of a stream of bytes with no record boundaries. N is not valid for the PIPE device type. If you do not specify the LRECL option, then by default SAS reads 256 bytes at a time from the file.
P	print format. On output, SAS writes carriage-control characters.
V	variable format. Each record ends with a newline character.
S370V	variable S370 record format (V).
S370VB	variable block S370 record format (VB).
S370VBS	variable block with spanned records S370 record format (VBS). If you specify RECFM=S3270VBS, then you should specify BLDSIZE=32760 and LRECL=32760 in order to avoid errors with records longer than 255 characters.

The RECFM= option is used for both input and output.

LOCKINTERNAL=AUTO | SHARED

specifies the SAS system locking that is to be used for the files that are listed in a FILENAME statement. LOCKINTERNAL can have one of the following values:

AUTO

locks a file so that in a SAS session, if a user has Write access to a file, then no other users can have Read or Write access to the file. If a user has Read access to a file, no other user can have Write access to the file, but multiple users can have Read access.

SHARED

locks a file so that in a SAS session, two users do not have simultaneous Write access to the file. The file can be shared simultaneously by one user who has Write access and multiple users who have Read access.

Default:

AUTO

UNBUF

tells SAS not to perform buffered writes to the file on any subsequent FILE statement. This option applies especially when you are reading from or writing to a data collection device. As explained in SAS Language Reference: Dictionary, it also prevents buffered reads on INFILE statements.

'pathname-1'...'pathname-n'

are pathnames for the files that you want to access with the same fileref. Use this form of the FILENAME statement when you want to concatenate filenames. Concatenation of filenames is available only for DISK files, so you do not have to specify the device-type. Separate the pathnames with either commas or blank spaces. Enclose each pathname in quotation marks. Character Substitutions in Pathnames shows character substitutions you can use when specifying a pathname. If the fileref that you are defining is to be used for input, then you can also use wildcards as described in Using Wildcards in Pathnames (Input Only). Remember that UNIX filenames are case-sensitive.

directory-name

specifies the directory that contains the files that you want to access. For more information, see Assigning a Fileref to a Directory (Using Aggregate Syntax).

access-method

can be CATALOG, SOCKET, FTP, SFTP, or URL. Device Information in the FILENAME Statement describes the information expected by these access methods.

access-information

differs according to the access method. Device Information in the FILENAME Statement shows the information appropriate to each access method.

CLEAR

clears the specified fileref or, if you specify _ALL_, clears all filerefs that are currently defined.

Note:   You cannot clear a fileref that is defined by an environment variable. Filerefs that are defined by environment variables are assigned for the entire SAS session.   

_ALL_

refers to all filerefs currently defined. You can use this keyword when you are listing or clearing filerefs.

LIST

writes to the SAS log the pathname of the specified fileref or, if you specify _ALL_, lists the definition for all filerefs that are currently defined. Filerefs defined as environment variables appear only if you have already used those filerefs in a SAS statement. If you are using the Bourne shell or the Korn shell, SAS cannot determine the name of a pre-opened file, so it displays the following string instead of a filename:

<File Descriptor number>

See Using Environment Variables to Assign Filerefs in UNIX Environments for more information.

File Locking

File locking of external files is controlled at the FILENAME statement level by the LOCKINTERNAL option. If you use the AUTO (default) value for LOCKINTERNAL, then SAS locks a file exclusively for one user who has Write access, or SAS locks a file non-exclusively for multiple users who have Read access. For example, if a file is opened in UPDATE or OUTPUT mode, then all other access from internal processes will be blocked. If a file is opened in INPUT mode, then multiple users can read the file, but UPDATE and OUTPUT functions are blocked.

If you use the SHARED value for LOCKINTERNAL, then SAS allows one user Write access to a file as well as allowing multiple users to read the file.

Device Information in the FILENAME Statement

The following table lists the relationship between device type or access method and the related external file.

http://hostname/file
http://hostname:portno/file

http://hostname/path-to-the-file
https://hostname/path-to-the-file 
http://hostname:port/path-to-the-file
 https://hostname:port/path-to-the-file

• Using External Files and Devices

• Printing and Routing Output

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