Birthday Calculation Post: 302272417

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Top Forums Shell Programming and Scripting Birthday Calculation Post 302272417 by methyl on Tuesday 30th of December 2008 02:01:38 PM

12-30-2008

Registered User

I agree with fpmurphy. [[ ]] is supported in Posix and required though I personally have only found it useful in the context of "while [[ condition ]]".

[[ and ]] are keywords with strict syntax rules. A keyword starts a command and should not be used in the wrong context or be quoted (or you can get unpredictable results).

[ and ] are commands. (On early unix they were executables).

More importantly.
What goes between [[ and ]] is a "conditional expression" with one set of syntax.
What goes between [ and ] is a simple "test" with a simpler syntax. See "man test" where it you'll see that [ ] is an equivalent to "test".

The two syntaxes are covered in the man page for a Posix shell. As it happens some of the basic syntax is common between the two types of condition giving the (wrong) impression that the syntax is always interchangable.

The big syntax difference is with boolean expressions.

BTW. fpmurphy script gives syntax errors with both Posix sh and ksh because the substring variables are from bash. I'm not convinced that the line starting "if [[" will give the right result either (not tested).

methyl

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LEARN ABOUT HPUX

rpccp_remove_profile

remove profile(1m)														remove profile(1m)

NAME

       remove profile - Removes all profile elements and the profile from the specified name service entry

SYNOPSIS

       rpccp remove profile  profile-entry-name [-s syntax]

OPTIONS

       Indicates  the  name  syntax of the entry name (optional). The only value for this option is the dce name syntax, which is the default name
       syntax. Until an alternative name syntax becomes available, specifying the -s option is unnecessary.

ARGUMENTS

       Indicates the name of the target profile.  For an entry in the local cell, you can omit the cell name and specify  only	the  cell-relative
       name.

DESCRIPTION

       The  remove  profile  command  removes a profile (and all of its elements) from the name service database. The entry name of the profile is
       required.

   Privilege Required
       You need write permission to the CDS object entry (the target profile entry).

NOTE

       This command is replaced at Revision 1.1 by the dcecp command and may not be provided in future releases of DCE.

EXAMPLES

       The following  commands	run  RPCCP  and  remove  the  profile  named  /.:/LandS/anthro/molly_o_profile:  $  rpccp  rpccp>  remove  profile
       /.:/LandS/anthro/molly_o_profile

RELATED INFORMATION

       Commands: add element(1m), remove element(1m), show profile(1m)

																remove profile(1m)