NM and CM callable.
Reads a user-defined label from a disk or magnetic tape file.
Operation Notes |
 |
When a disk file is opened, user labels can be read from, or written to,
in any order, at any time, regardless of access capabilities
to the rest of the file. A disk file can have <=254 128-half word
user-defined labels.
A magnetic tape file (if labeled) must
be labeled with an ANSI-standard or IBM-standard label. The operating system
automatically skips over any unread user-defined labels when
the first FREAD intrinsic call for files is issued.
To read a user-defined label, you should call the FREADLABEL intrinsic
immediately after an FOPEN/HPFOPEN intrinsic has opened
the file. The user-defined label must be 40 half words in length to
conform to the length of the ANSI-standard or IBM-standard label.
