OSF DCE Administration Guide--Core Components

Using the DCE Control Program Command Language
foreach s [dts catalog] {
if {[catch {dts show $s} dts_sh_out] != 0} {
continue
}
set p [attrlist getval $dts_sh_out -type provider]
if {[string match $p "yes"] == 1} {
set provider "yes"
set server $s
break
}
set provider "no"
}
2.9.4 Testing with Patterns Before Execution with case
Some commands return a list such as a list of objects in a directory or a list of servers
running on a host system. You can use the case command to test a list or string for
specific patterns such as the name of a particular object or server. On detecting a
specified pattern, the case command then executes a script associated with the pattern
detected. The syntax for the case command is
case string in pattern {script} pattern {script}
The case command looks in string for pattern and executes {script}. The word in may
be omitted. The following example illustrates how the case command works:
dcecp> set x {one ten twenty}
one ten twenty
dcecp> foreach el $x {case $el in one {puts script1} two {puts script2}}
script1
dcecp>
The case command first checks in $x for the pattern one. On finding this pattern, the
associated script echoes script 1 on the display. When it finds no more matches, the case
command ends.
For a more practical example, say you run a dcecp command that lists all the servers on a
particular system. You could search the list for particular server names and execute a
script that appends each name to a particular file, as follows:
case $x in server1 {lappend filename1} server2 {lappend filename2}
If your list of patterns is lengthy and likely to break across lines, you can prevent
newlines from being interpreted as separators by enclosing the entire list of target
patterns and scripts in braces. This has the additional benefit of preventing variable and
command substitutions in the braced list.
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