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Rc Functions

To date, the CSA libraries provide the functions listed below. Providing documentation for all of them in this document is going to be a major effort. In the meantime please refer to the explanatory comments that are contained in the library files, and to the example programs.

 csaAssign 
 csaAuth.send 
 csaAwk 
 csaAwk.cgi 
 csaBugReport 
 csaCheck.special 
 csaChop 
 csaCleanup 
 csaClient 
 csaCollapse 
 csaCommit 
 csaConceal 
 csaCookie.set 
 csaDebug 
 csaExit 
 csaExit.bdata 
 csaExit.cdata 
 csaExit.pcdata 
 csaExit.env 
 csaExit.fault 
 csaExit.http 
 csaExit.location 
 csaExit.needauth 
 csaExit.ok 
 csaExit.session 
 csaExit.table 
 csaExit.value 
 csaGetArgs 
 csaHttp.header 
 csaHttp.referrers 
 csaHttp.status 
 csaIndex 
 csaIsConfirmed 
 csaIsDate 
 csaIsFullPath 
 csaIsInteractive 
 csaIsWeb 
 csaLoadLib 
 csaLock 
 csaMkTemp 
 csaNew 
 csaOnCommit 
 csaOpen 
 csaPrintMsg 
 csaSession.set 
 csaSetClear 
 csaSetTime 
 csaSource 
 csaStatus 
 csaSubshell 
 csaSum 
 csaSwap 
 csaSystem 
 csaTemplate 
 csaTest.set 
 csaTest.unset 
 csaTplProc 
 csaTrapFile 
 csaTrue 
 csaUniq 
 csaUnlist 
 csaUnlock 
 

Shell function overrides.

The rc shell, on which CSA is largely based, exports all names and function definitions to the program environment by default. Function definitions, in particular, may cause the environment to become really big and cluttered. To try and mitigate this problem, different CSA shell libraries often re-define previously defined shell functions. For instance, the csaExit.fault function is defined in both mainlib.rc and cgilib.rc. In all cases the function serves the same purpose: exiting on errors. The way it accomplishes its job, however, may be different in the three cases. A command-line shell script will only load mainlib.rc, and the version of csaExit.fault contained in that library will simply exit non-zero (after doing some housekeeping) if called in that context. A CGI program, however, beside loading mainlib.rc will also load cgilib.rc. This second library will provide its own re-definition of csaExit.fault. The latter, if called by the CGI program, will do the housekeeping, send an error HTML page to the client and exit non-zero. In this way, that is by re-using the same function names for different context-specific code, I managed to:

  1. keep the program API simple and consistent across different contexts.
  2. keep the program environment small, as each re-definition replaces the previous one.


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