z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

ln
Localization
Exit Values
2. spawn() will access the file for name1 unaware that there is a symbolic link
already established. It will access the name2 file by its underlying vnode, not
the name2 handle.
3. If the sticky bit is on for the name2 file, spawn() will do the MVS search for
name1 (the only name it has to work with).
Symbolic and external links with a sticky bit:
Note: DLLs, and all flavors of spawn() and exec(), follow the same processing as
described below. Where it says exec(), it covers all forms of module loading.
1. External links:
exec() does a stat() on the passed filename. stat() does the search, not exec().
If the filename is an external link, then stat() fails with a unique reason code
which causes exec() to read the external link. If the external link name is a valid
PDS member name (1–8 alphanumeric/special characters), then exec() will
attempt to locate the module in the MVS search order. If it cannot be found,
exec() fails.
The external link is normally used when you want to set the sticky bit on for a
file name which is longer than 8 characters or contains characters unacceptable
for a PDS member name.
2. Symbolic links:
If the filename you specify is a symbolic link, and exec() sees the sticky bit on,
then it will truncate any dot qualifiers. So, as long as the base filename is an
acceptable PDS member name, the need to set up links in order to get exec()
to go to the MVS search order should not be an issue.
For example, if you have a file named java.jll, when you put the sticky bit on,
exec() will attempt to load JAVA. If exec() cannot find JAVA, it will revert to
using the java.jll file in the file system.
The important thing to understand is that exec() never sees the name that the
symbolic link resolves to even though it can see the stat() data for the final file.
ln uses the following localization environment variables:
v LANG
v LC_ALL
v LC_CTYPE
v LC_MESSAGES
v LC_SYNTAX
v NLSPATH
See Appendix F for more information.
0 All requested links were established successfully.
1 Failure due to any of the following:
v An argument had a trailing / but was not the name of a directory.
v A file could not be found.
v An input file could not be opened for reading.
v An output file could not be created or opened for output.
v The new link file already exists.
v A link could not be established.
v A read error occurred on an input file.
v A write error occurred on an output file.
350 z/OS V1R9.0 UNIX System Services Command Reference