This chapter describes, through program examples, various
ways that you can use file system intrinsics to transfer data from
your program to a disk file or a device file. This chapter is intended
to illustrate topics introduced in chapter 7, "Record Selection
and Data Transfer". This chapter is divided into the following topics:
"Sequential Access and Random Access" discusses two common methods
of record selection and data transfer, and uses examples to
illustrate the use of the FWRITE and FWRITEDIR
intrinsics.
"Writing to $STDLIST" discusses how your program can use the
PRINT and FWRITE intrinsics to write data from your
program to the job/session standard list device, $STDLIST.
An example illustrates the use of the PRINT intrinsic to
write a character string to $STDLIST.
"Writing Messages to the system console" discusses how your
program can send messages from your program to the system console,
and request a reply from the operator. Examples illustrate the use of
the PRINTOP and PRINTOPREPLY intrinsics.
"Writing to a Magnetic Tape File" discusses how you can write data
to two kinds of magnetic tape files: unlabeled tape files and labeled
tape files. Examples illustrate the use of the FWRITE
intrinsic to write data to both types of tape files.
"Writing a File Label to a Labeled Tape File" provides an example
of using the FWRITELABEL intrinsic to write a user-defined
file label to a labeled magnetic tape file.