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17: <div class=Section1><span style='font-size:12.0pt;font-family:Arial;'><b><i><br clear=ALL style='page-break-before:always'>
18: </i></b></span>
19: <h2><a name="_Toc421867053">Session Three: Roles and lonnet/loncommon useful
20: functions (Guy)</a></h2>
21: <h3><a name=name></a><a name="_Toc421867054">NAME</a></h3>
22: <p>Apache::lonnet - Subroutines to ask questions about things in the network.</p>
23: <div align=center style='text-align:center'>
24: <hr size=2 width="100%" align=center>
25: </div>
26: <h3><a name=synopsis></a><a name="_Toc421867055">SYNOPSIS</a></h3>
27: <p>Invoked by other LON-CAPA modules, when they need to talk to or about objects
28: in the network.</p>
29: <pre> &Apache::lonnet::SUBROUTINENAME(ARGUMENTS);</pre>
30: <p>Common parameters:</p>
31: <ul type=disc>
32: <li>$uname : an internal username (if $cname expecting a course Id specifically)
33: </li>
34: <li>$udom : a domain (if $cdom expecting a course's domain specifically) </li>
35: <li>$symb : a resource instance identifier </li>
36: <li>$namespace : the name of a .db file that contains the data needed or being
37: set. </li>
38: </ul>
39: <div align=center style='text-align:center'>
40: <hr size=2 width="100%" align=center>
41: </div>
42: <h3><a name=introduction></a><a name="_Toc421867056">INTRODUCTION</a></h3>
43: <p>This module provides subroutines which interact with the lonc/lond (TCP)
44: network layer of LON-CAPA. And Can be used to ask about - classes - users
45: - resources</p>
46: <p>For many of these objects you can also use this to store data about them
47: or modify them in various ways.</p>
48: <p>This is part of the LearningOnline Network with CAPA project described at
49: <a
50: href="http://www.lon-capa.org./">http://www.lon-capa.org.</a></p>
51: <div align=center style='text-align:center'>
52: <hr size=2 width="100%" align=center>
53: </div>
54: <h3><a name="return_messages"></a><a name="_Toc421867057">RETURN MESSAGES</a></h3>
55: <ul type=disc>
56: <li>con_lost : unable to contact remote host </li>
57: <li>con_delayed : unable to contact remote host, message will be delivered
58: when the connection is brought back up </li>
59: <li>con_failed : unable to contact remote host and unable to save message
60: for later delivery </li>
61: <li>error: : an error a occured, a description of the error follows the :
62: </li>
63: <li>no_such_host : unable to fund a host associated with the user/domain that
64: was requested </li>
65: </ul>
66: <div align=center style='text-align:center'>
67: <hr size=2 width="100%" align=center>
68: </div>
69: <h3><a name="session_environment_functions"></a><a name="_Toc421867058">Session
70: Environment Functions</a></h3>
71: <ul type=disc>
72: <li><code><span style='font-family:
73: Courier'>appenv(%hash)</span></code> : the value of %hash is written to the
74: user envirnoment file, and will be restored for each access this user makes
1.3 ! albertel 75: during this session, also modifies the %env for the current process </li>
1.2 bowersj2 76: <li><code><span style='font-family:
77: Courier'>delenv($regexp)</span></code> : removes all items from the session
78: environment file that matches the regular expression in $regexp. The values
1.3 ! albertel 79: are also delted from the current processes %env. </li>
1.2 bowersj2 80: </ul>
81: <h3><a name="user_information"></a><a name="_Toc421867059">User Information</a></h3>
82: <ul type=disc>
83: <li><code><span style='font-family:
84: Courier'>queryauthenticate($uname,$udom)</span></code> : try to determine
85: user's current authentication scheme </li>
86: <li><code><span style='font-family:
87: Courier'>authenticate($uname,$upass,$udom)</span></code> : try to authenticate
88: user from domain's lib servers (first use the current one), $upass should
89: be the users password </li>
90: <li><code><span style='font-family:
91: Courier'>homeserver($uname,$udom)</span></code> : find the server which has
92: the user's directory and files (there must be only one) . This caches the
93: answer and also caches if there is an error.</li>
94: <li><code><span style='font-family:
95: Courier'>idget($udom,@ids)</span></code> : find the usernames behind a list
96: of IDs (IDs are a unique resource in a domain, there must be only 1 ID per
97: username, and only 1 username per ID in a specific domain) (returns hash:
98: id=>name,id=>name) </li>
99: <li><code><span style='font-family:
100: Courier'>idrget($udom,@unames)</span></code> : find the IDs behind a list
101: of usernames (returns hash: name=>id,name=>id) </li>
102: <li><code><span style='font-family:
103: Courier'>idput($udom,%ids)</span></code> : store away a list of names and
104: associated IDs </li>
105: <li><code><span style='font-family:
106: Courier'>rolesinit($udom,$username,$authhost)</span></code> : get user privileges
107: </li>
108: <li><code><span style='font-family:
109: Courier'>usection($udom,$uname,$cname)</span></code> : finds the section
110: of student in the course $cname, return section name/number or '' for ``not
111: in course'' and '-1' for ``no section'' </li>
112: <li><code><span style='font-family:
113: Courier'>userenvironment($udom,$uname,@what)</span></code> : gets the values
114: of the keys passed in @what from the requested user's environment, returns
115: a hash </li>
116: </ul>
117: <h3><a name="user_roles"></a><a name="_Toc421867060">User Roles</a></h3>
118: <ul type=disc>
119: <li><code><span style='font-family:
120: Courier'>allowed($priv,$uri)</span></code> : check for a user privilege;
121: returns codes for allowed actions F: full access U,I,K: authentication modes
122: (cxx only) '': forbidden 1: user needs to choose course 2: browse allowed
123: </li>
124: <li><code><span style='font-family:
125: Courier'>definerole($rolename,$sysrole,$domrole,$courole)</span></code> :
126: define role; define a custom role rolename set privileges in format of lonTabs/roles.tab
127: for system, domain, and course level </li>
128: <li><code><span style='font-family:
129: Courier'>plaintext($short)</span></code> : return value in %prp hash (rolesplain.tab);
130: plain text explanation of a user role term </li>
131: </ul>
132: <h3><a name="user_modification"></a><a name="_Toc421867061">User Modification</a></h3>
133: <ul type=disc>
134: <li><code><span
135: style='font-family:Courier'>assignrole($udom,$uname,$url,$role,$end,$start)</span></code>
136: : assign role; give a role to a user for the level given by URL. Optional
137: start and end dates (leave empty string or zero for ``no date'') </li>
138: <li><span style='font-family:
139: "Courier New"'>changepass($uname,$udom,$currentpass,$newpass,$server):</span>
140: attempts to change a users, password, possible return values are: <span
141: style='font-family:"Courier New"'>ok, pwchange_failure, non_authorized, auth_mode_error,
142: unknown_user, refused</span></li>
143: <li><code><span
144: style='font-family:Courier'>modifyuserauth($udom,$uname,$umode,$upass)</span></code>
145: : modify user authentication </li>
146: <li><code><span
147: style='font-family:Courier'>modifyuser($udom,$uname,$uid,$umode,$upass,$first,$middle,$last,$gene)</span></code>
148: : modify user </li>
149: <li>modifystudent($udom,$uname,$uid,$umode,$upass,$first,$middle,$last,$gene,$usec,
150: $end,$start) : modify student </li>
151: <li><code><span
152: style='font-family:Courier'>assigncustomrole($udom,$uname,$url,$rdom,$rnam,$rolename,$end,$start)</span></code>
153: : assign custom role; give a custom role to a user for the level given by
154: URL. Specify name and domain of role author, and role name </li>
155: <li><code><span
156: style='font-family:Courier'>revokerole($udom,$uname,$url,$role)</span></code>
157: : revoke a role for url </li>
158: <li><code><span
159: style='font-family:Courier'>revokecustomrole($udom,$uname,$url,$role)</span></code>
160: : revoke a custom role </li>
161: </ul>
162: <h3><a name="course_infomation"></a><a name="_Toc421867062">Course Infomation</a></h3>
163: <ul type=disc>
164: <li><code><span style='font-family:
165: Courier'>coursedescription($courseid)</span></code> : course description
166: </li>
167: <li><span style='font-family:
168: "Courier New"'>courseresdata($coursenum,$coursedomain,@which) :</span> request
169: for current parameter setting for a specific course, @what should be a list
170: of parameters to ask about. This routine caches answers for 5 minutes.</li>
171: </ul>
172: <h3><a name="course_modification"></a><a name="_Toc421867063">Course Modification</a></h3>
173: <ul type=disc>
174: <li><code><span
175: style='font-family:Courier'>writecoursepref($courseid,%prefs)</span></code>
176: : write preferences (environment database) for a course </li>
177: <li><code><span
178: style='font-family:Courier'>createcourse($udom,$description,$url)</span></code>
179: : make/modify course </li>
180: </ul>
181: <h3><a name="resource_subroutines"></a><a name="_Toc421867064">Resource Subroutines</a></h3>
182: <ul type=disc>
183: <li><code><span style='font-family:
184: Courier'>subscribe($fname)</span></code> : subscribe to a resource, returns
185: URL if possible (probably should use repcopy instead) </li>
186: <li><code><span style='font-family:
187: Courier'>repcopy($filename)</span></code> : subscribes to the requested file,
188: and attempts to replicate from the owning library server, Might return HTTP_SERVICE_UNAVAILABLE,
189: HTTP_NOT_FOUND, FORBIDDEN, OK, or HTTP_BAD_REQUEST, also attempts to grab
190: the metadata for the resource. Expects the local filesystem pathname (/home/httpd/html/res/....)
191: </li>
192: </ul>
193: <h3><a name="resource_information"></a><a name="_Toc421867065">Resource Information</a></h3>
194: <ul type=disc>
195: <li>EXT($varname,$symb,$udom, $uname) : evaluates and returns the value of
196: a vairety of different possible values, $varname should be a request string,
197: and the other parameters can be used to specify who and what one is asking
198: about. </li>
199: </ul>
200: <p><span style='font-size:10.0pt'>Possible values for $varname are environment.lastname
201: (or other item from the environment hash), user.name (or someother aspect
202: about the user), resource.0.maxtries (or some other part and parameter of
203: a resource)</span></p>
204: <ul type=disc>
205: <li><code><span
206: style='font-family:Courier'>directcondval($number)</span></code> : get current
207: value of a condition; reads from a state string </li>
208: <li><code><span
209: style='font-family:Courier'>condval($condidx)</span></code> : value of condition
210: index based on state </li>
211: <li><code><span
212: style='font-family:Courier'>metadata($uri,$what,$liburi,$prefix,$depthcount)</span></code>
213: : request a resource's metadata, $what should be either a specific key,
214: or either 'keys' (to get a list of possible keys) or 'packages' to get a
215: list of packages that this resource currently uses, the last 3 arguments
216: are only used internally for recursive metadata. This function automatically
217: caches all requests</li>
218: <li><code><span
219: style='font-family:Courier'>metadata_query($query,$custom,$customshow)</span></code>
220: : make a metadata query against the network of library servers; returns
221: file handle of where SQL and regex results will be stored for query</li>
222: <li><code><span
223: style='font-family:Courier'>symbread($filename)</span></code> : return symbolic
224: list entry (filename argument optional); returns the data handle </li>
225: <li><span style='font-family:
226: "Courier New"'>symbverify($symb,$thisfn):</span> verifies that $symb actually
227: exists and is a possible symb for the URL in $thisfn, returns a 1 on success,
228: 0 on failure, user must be in a course, as it assumes the existance of the
1.3 ! albertel 229: course init hash, and uses $env('request.course.id'}</li>
1.2 bowersj2 230: <li><span style='font-family:
231: "Courier New"'>symbclean($symb):</span> removes versions numbers from a symb,
232: returns the cleaned symb</li>
233: <li><span style='font-family:
234: "Courier New"'>is_on_map($uri) :</span> checks if the $uri is somewhere on
235: the current course map, user must be in a course for it to work</li>
236: <li><code><span
237: style='font-family:Courier'>numval($salt)</span></code> : return random seed
238: value (addend for rndseed) </li>
239: <li><code><span
240: style='font-family:Courier'>rndseed($symb,$courseid,$udom,$username)</span></code>
241: : create a random sum; returns a random seed, all arguments are optional,
242: if they aren't sent it uses the environment to derive them. Note: if symb
243: isn't sent and it can't get one from &symbread it will use the current
244: time as its return value </li>
245: <li><code><span
246: style='font-family:Courier'>ireceipt($funame,$fudom,$fucourseid,$fusymb)</span></code>
247: : return unique, unfakeable, receipt </li>
248: <li><code><span
249: style='font-family:Courier'>receipt()</span></code> : API to ireceipt working
1.3 ! albertel 250: off of env values; given out to users </li>
1.2 bowersj2 251: <li><code><span
252: style='font-family:Courier'>countacc($url)</span></code> : count the number
253: of accesses to a given URL </li>
254: <li><code><span
255: style='font-family:Courier'>checkout($symb,$tuname,$tudom,$tcrsid)</span></code>
256: : creates a record of a user having looked at an item, most likely printed
257: out or otherwise using a resource </li>
258: <li><code><span
259: style='font-family:Courier'>checkin($token)</span></code> : updates that
260: a resource has beeen returned (a hard copy version for instance) and returns
261: the data that $token was Checkout with ($symb, $tuname, $tudom, and $tcrsid)
262: </li>
263: <li><code><span
264: style='font-family:Courier'>expirespread($uname,$udom,$stype,$usymb)</span></code>
265: : set expire date for spreadsheet </li>
266: <li><code><span
267: style='font-family:Courier'>devalidate($symb)</span></code> : devalidate
268: temporary spreadsheet calculations, forcing spreadsheet to reevaluate the
269: resource scores next time. </li>
270: </ul>
271: <h3><a name="storing/retreiving_data"></a><a name="_Toc421867066"><span
272: style='"storing\/retreiving_data"'>Storing/Retrieving Data</span></a></h3>
273: <ul type=disc>
274: <li><code><span
275: style='font-family:Courier'>store($storehash,$symb,$namespace,$udom,$uname)</span></code>
276: : stores hash permanently for this url; hashref needs to be given and should
277: be a \%hashname; the remaining args aren't required and if they aren't passed
1.3 ! albertel 278: or are '' they will be derived from the env </li>
1.2 bowersj2 279: <li><code><span
280: style='font-family:Courier'>cstore($storehash,$symb,$namespace,$udom,$uname)</span></code>
281: : same as store but uses critical subroutine </li>
282: <li><code><span
283: style='font-family:Courier'>restore($symb,$namespace,$udom,$uname)</span></code>
284: : returns hash for this symb; all args are optional </li>
285: <li><code><span
286: style='font-family:Courier'>tmpstore($storehash,$symb,$namespace,$udom,$uname)</span></code>
287: : storage that works very similar to store/cstore, but all data is stored
288: in a temporary location and can be reset using tmpreset, $storehash should
289: be a hash reference, returns nothing on success </li>
290: <li><code><span
291: style='font-family:Courier'>tmprestore($symb,$namespace,$udom,$uname)</span></code>
292: : storage that works very similar to restore, but all data is stored in
293: a temporary location and can be reset using tmpreset. Returns a hash of
294: values on success, error string otherwise. </li>
295: <li><code><span
296: style='font-family:Courier'>tmpreset($symb,$namespace,$udom,$uname)</span></code>
297: : temporary storage reset, deltes all keys for $symb form the temporary
298: storage hash. </li>
299: <li><code><span
300: style='font-family:Courier'>get($namespace,$storearr,$udom,$uname)</span></code>
301: : returns hash with keys from array reference filled in from namesp ($udomain
302: and $uname are optional) </li>
303: <li><code><span
304: style='font-family:Courier'>del($namespace,$storearr,$udom,$uname)</span></code>
305: : deletes keys out of array from namesp ($udomain and $uname are optional)
306: </li>
307: <li><code><span
308: style='font-family:Courier'>dump($namespace,$udom,$uname,$regexp)</span></code>
309: : dumps the complete (or key matching regexp) namespace into a hash ($udomain,
310: $uname and $regexp are optional) </li>
311: <li><code><span
312: style='font-family:Courier'>put($namespace,$storehash,$udomain,$uname)</span></code>
313: : stores hash in namesp ($udomain and $uname are optional) </li>
314: <li><code><span
315: style='font-family:Courier'>cput($namespace,$storehash,$udomain,$uname)</span></code>
316: : critical put ($udomain and $uname are optional) </li>
317: <li><code><span
318: style='font-family:Courier'>eget($namespace,$storearr,$udomain,$uname)</span></code>
319: : returns hash with keys from array reference filled in from namesp (encrypts
320: the return communication) ($udomain and $uname are optional) </li>
321: <li><code><span
322: style='font-family:Courier'>log($udom,$name,$home,$message)</span></code>
323: : write to permanent log for user; use critical subroutine </li>
324: </ul>
325: <h3><a name="network_status_functions"></a><a name="_Toc421867067">Network Status
326: Functions</a></h3>
327: <ul type=disc>
328: <li><code><span
329: style='font-family:Courier'>dirlist($uri)</span></code> : return directory
330: list based on URI </li>
331: <li><code><span
332: style='font-family:Courier'>spareserver()</span></code> : find server with
333: least workload from spare.tab </li>
334: </ul>
335: <h3><a name="apache_request"></a><a name="_Toc421867068">Apache Request</a></h3>
336: <ul type=disc>
337: <li><code><span
338: style='font-family:Courier'>ssi($url,%hash)</span></code> : server side include,
339: does a complete request cycle on url to localhost, posts hash </li>
340: </ul>
341: <h3><a name="data_to_string_to_data"></a><a name="_Toc421867069">Data to String
342: to Data</a></h3>
343: <ul type=disc>
344: <li><code><span
345: style='font-family:Courier'>hash2str(%hash)</span></code> : convert a hash
346: into a string complete with escaping and '=' and '&' separators, supports
347: elements that are arrayrefs and hashrefs </li>
348: <li><code><span
349: style='font-family:Courier'>hashref2str($hashref)</span></code> : convert
350: a hashref into a string complete with escaping and '=' and '&' separators,
351: supports elements that are arrayrefs and hashrefs </li>
352: <li><code><span
353: style='font-family:Courier'>arrayref2str($arrayref)</span></code> : convert
354: an arrayref into a string complete with escaping and '&' separators,
355: supports elements that are arrayrefs and hashrefs </li>
356: <li><code><span
357: style='font-family:Courier'>str2hash($string)</span></code> : convert string
358: to hash using unescaping and splitting on '=' and '&', supports elements
359: that are arrayrefs and hashrefs </li>
360: <li><code><span
361: style='font-family:Courier'>str2array($string)</span></code> : convert string
362: to hash using unescaping and splitting on '&', supports elements that
363: are arrayrefs and hashrefs </li>
364: </ul>
365: <h3><a name="logging_routines"></a><a name="_Toc421867070">Logging Routines</a></h3>
366: <p>These routines allow one to make log messages in the lonnet.log and lonnet.perm
367: logfiles.</p>
368: <ul type=disc>
369: <li><code><span
370: style='font-family:Courier'>logtouch()</span></code> : make sure the logfile,
371: lonnet.log, exists </li>
372: <li><code><span
373: style='font-family:Courier'>logthis()</span></code> : append message to the
374: normal lonnet.log file, it gets preiodically rolled over and deleted. </li>
375: <li><code><span
376: style='font-family:Courier'>logperm()</span></code> : append a permanent
377: message to lonnet.perm.log, this log file never gets deleted by any automated
378: portion of the system, only messages of critical importance should go in
379: here. </li>
380: </ul>
381: <h3><a name="general_helper_routines"></a><a name="_Toc421867071">General File
382: Helper Routines</a></h3>
383: <ul type=disc>
384: <li><code><span
385: style='font-family:Courier'>getfile($file)</span></code> : serves up a file,
386: returns the contents of a file or -1; replicates and subscribes to the file
387: </li>
388: <li><code><span
389: style='font-family:Courier'>filelocation($dir,$file)</span></code> : returns
390: file system location of a file based on URI; meant to be ``fairly clean''
391: absolute reference, $dir is a directory that relative $file lookups are
392: to looked in ($dir of /a/dir and a file of ../bob will become /a/bob) </li>
393: <li><code><span
394: style='font-family:Courier'>hreflocation($dir,$file)</span></code> : returns
395: file system location or a URL; same as filelocation except for hrefs </li>
396: <li><code><span
397: style='font-family:Courier'>declutter()</span></code> : declutters URLs (remove
398: docroot, beginning slashes, 'res' etc) </li>
399: </ul>
400: <h3><a name="_Toc421867072">HTTP Helper Routines</a></h3>
401: <ul type=disc>
402: <li><code><span
403: style='font-family:Courier'>escape()</span></code> : unpack non-word characters
404: into CGI-compatible hex codes </li>
405: <li><code><span
406: style='font-family:Courier'>unescape()</span></code> : pack CGI-compatible
407: hex codes into actual non-word ASCII character </li>
408: </ul>
409: </div>
410: <h1> </h1>
411: <h3><a name="underlying_communication_routines_(shoul"></a><a
412: name="_Toc421867073">Private: Underlying communication routines (Shouldn't call)</a></h3>
413: <ul type=disc>
414: <li><code><span style='font-family:
415: Courier'>subreply()</span></code> : tries to pass a message to lonc, returns
416: con_lost if incapable </li>
417: <li><code><span style='font-family:
418: Courier'>reply()</span></code> : uses subreply to send a message to remote
419: machine, logs all failures </li>
420: <li><code><span style='font-family:
421: Courier'>critical()</span></code> : passes a critical message to another
422: server; if cannot get through then place message in connection buffer directory
423: and returns con_delayed, if incapable of saving message, returns con_failed
424: </li>
425: <li><code><span style='font-family:
426: Courier'>reconlonc()</span></code> : tries to reconnect lonc client processes.
427: </li>
428: </ul>
429: <h3><a name="resource_access_logging"></a><a name="_Toc421867074">Private: Resource
430: Access Logging</a></h3>
431: <ul type=disc>
432: <li><code><span style='font-family:
433: Courier'>flushcourselogs()</span></code> : flush (save) buffer logs and access
434: logs </li>
435: <li><code><span style='font-family:
436: Courier'>courselog($what)</span></code> : save message for course in hash
437: </li>
438: <li><code><span style='font-family:
439: Courier'>courseacclog($what)</span></code> : save message for course using
440: &courselog(). Perform special processing for specific resource types (problems,
441: exams, quizzes, etc). </li>
442: <li><code><span style='font-family:
443: Courier'>goodbye()</span></code> : flush course logs and log shutting down;
444: it is called in srm.conf as a PerlChildExitHandler </li>
445: </ul>
446: <h3><a name=other></a><a name="_Toc421867075">Private: Other</a></h3>
447: <p><code><span style='font-family:"Courier New"'>symblist($mapname,%newhash)</span></code><span
448: style='font-family:"Courier New"'> :</span> update symbolic storage links </p>
449: <h3><a name="_Toc421867076">Coding Guidelines</a></h3>
450: <p class=H5><span style='layout-grid-mode:
451: both'>Things to keep in mind while coding handlers for LON-CAPA </span></p>
452: <p><span
453: style='font-size:14.0pt'>1.<span style='font:7.0pt "Times New Roman"'>
454: </span></span><span style='font-size:14.0pt'>DON'T write to Access machine disks
455: with permanent data, use store/restore </span></p>
456: <p><span
457: style='font-size:14.0pt'>2.<span style='font:7.0pt "Times New Roman"'>
458: </span></span><span style='font-size:14.0pt'>DON'T </span><span
459: style='font-size:14.0pt;font-family:"Courier New"'>use print()</span><span
460: style='font-size:14.0pt'>, use </span><span style='font-size:14.0pt;font-family:
461: "Courier New"'>$request->print()</span><span style='font-size:14.0pt'> </span></p>
462: <p><span
463: style='font-size:14.0pt'>3.<span style='font:7.0pt "Times New Roman"'>
464: </span></span><span style='font-size:14.0pt'>DON'T launch children </span></p>
465: <p><span
466: style='font-size:14.0pt'>4.<span style='font:7.0pt "Times New Roman"'>
467: </span></span><span style='font-size:14.0pt'>DO use </span><span
468: style='font-size:14.0pt;font-family:"Courier New"'>$Apache::lonnet::perlvar{'lonDaemons'}/tmp</span><span
469: style='font-size:14.0pt'> for temporary data. </span></p>
470: <p><span
471: style='font-size:14.0pt'>5.<span style='font:7.0pt "Times New Roman"'>
472: </span></span><span style='font-size:14.0pt'>DO query the return value of every
473: file operation. </span></p>
474: <p><span
475: style='font-size:14.0pt'>6.<span style='font:7.0pt "Times New Roman"'>
476: </span></span><span style='font-size:14.0pt'>DO </span><span style='font-size:
477: 14.0pt;font-family:"Courier New"'>use strict;</span><span style='font-size:
478: 14.0pt'> </span></p>
479: <p><span
480: style='font-size:14.0pt'>7.<span style='font:7.0pt "Times New Roman"'>
481: </span></span><span style='font-size:14.0pt'>DO </span><span style='font-size:
482: 14.0pt;font-family:"Courier New"'>use strict;</span><span style='font-size:
483: 14.0pt'> </span></p>
484: <p><span
485: style='font-size:14.0pt'>8.<span style='font:7.0pt "Times New Roman"'>
486: </span></span><span style='font-size:14.0pt'>DO familiarize your self with the
487: functions in </span><span style='font-size:14.0pt;font-family:"Courier New"'>lonnet.pm</span><span
488: style='font-size:14.0pt'> and use them to communicate with other servers and when
489: you handler needs to ask questions. </span></p>
490: <p>9.<span
491: style='font:7.0pt "Times New Roman"'> </span><span
492: style='font-size:14.0pt'>DON'T use </span><span style='font-size:14.0pt;
493: font-family:"Courier New"'>&Apache::lonnet::reply()</span><span
494: style='font-size:14.0pt'> </span></p>
495: <br
496: clear=ALL style='page-break-before:always;'>
497: <div class=Section2> </div>
498: </body>
499: </html>
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