Accessing Files Programmer's Guide (32650-90885)

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9 Reading from a File
This chapter describes, through program examples, various ways that you can use file
system intrinsics to transfer data to your program from a disk file or 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 FREAD and
FREADDIR intrinsics.
• "Reading from $STDIN" discusses how your program can use the READ, READX, and
FREAD intrinsics to read data from the job/session standard input device, $STDIN. An
example illustrates the use of the READ intrinsic to read a character string from
$STDIN.
• "Reading from a Magnetic Tape File" provides an example of using the FREAD intrinsic
to read data from file located on magnetic tape.
• "Reading a File Label from a Labeled Tape File" provides an example of using the
FREADLABEL intrinsic to read a user-defined file label located on a labeled magnetic
tape file.