TweetFollow Us on Twitter

Function Logging
Volume Number:8
Issue Number:7
Column Tag:C Workshop

Function Logging in Think C

For debugging, optimizing, and better understanding a program’s execution path

By Eric Shapiro, Ann Arbor, Michigan

About the author

Eric Shapiro’s works include Business Simulator®, EzTape®, and two new QuickTime™ programs: Spectator™, a screen recorder from Baseline Publishing and VideoBeep™, a silly Control Panel from Sound Source Unlimited.

Eric has taught Mac programming seminars for Apple and developed the course materials for Apple’s Macintosh Device Driver seminar. He is best known, however, as the author of everyones favorite singing trash can, The Grouch.

Overview

This article presents a simple way to log all function calls into a text file using Think C 5.0. The technique presented here is useful for debugging, optimizing, and obtaining a better understanding of a program’s execution path.

History

In the old days before source level debugging, function logging was an important way to debug Mac programs. On one of my first Mac projects, I remember sending function names out the serial port to a machine running a terminal program in order to figure out where the program was crashing. At MacHack this year, Marshall Clow from Hewlett Packard showed how to log function calls to MacsBug in MPW. Preferring Think C to MPW, I decided that I’d do a similar project for Think C. This article presents the results.

To Use the Logger

If all you want to do is use the function logger, here’s what you need to do:

• Add the file LogToFile.c to your Think C project.

• Add the file ANSI or ANSI-Small to your project (for some string utilities).

• Turn both the profiling and stack frame options on for the project.

• Call LogInit during program initialization (with appropriate parameters).

• Call LogDInit during program de-initialization.

• Recompile your code.

That’s all there is to it! You can control logging more precisely as follows:

• The following line of code turns profiling on for an entire file (if it appears outside of all functions) or for a single routine (if it appears within a function):

/* 1 */
 #pragma options( profile, force_frame )

• Likewise, the following line of code turns profiling off:

/* 2 */
 #pragma options( !profile, !force_frame ) 

• You can determine if logging is active at compile-time using:

/* 3 */
      #if _option( profile )

• Call SetLogState( true ) or SetLogState( false ) to turn logging on or off during program execution. You can do this via a menu selection, for example.

• Call SetLogFlush( true ) or SetLogFlush( false ) to turn flushing on or off during program execution. Performance suffers considerably when flushing is active, but it can help find the location where a crash occurs.

Note: Writing to disk when debugging a program can be a dangerous activity. Be sure you have adequate backups before trying any new debugging technique.

Note: By default, the function logger handles calling depths up to 100 levels. This should be sufficient for all but the most recursive programs. You can change the constant kMaxLogDepth to control the maximum depth.

How The Logger Works

When profiling is active, Think C generates a call to the function _profile_ at the beginning of every function call. Actually, only functions that generate stack frames call _profile_, which is why we turn on the stack frame option as well (stack frames are described below). The _profile_ function has the following form:

/* 4 */
void _profile_( void *functionNamePString )

The first version of _profile_ I wrote simply logged the function name to a file. While this is adequate for some uses, I really wanted to create an indented list of function calls so a programmer can tell exactly who called each function. To do this, our code needs to be notified when a function exits as well as when it is entered. Here’s where life gets a bit complicated.

Unfortunately, Think C’s profiler doesn’t generate a function call whenever a function exits. I looked at Think C’s profiler source code and used a similar technique for my logger. The technique involves replacing return addresses on the stack with the address of our own routine. When a function exits via an rts instruction, it will unknowingly call our exit handler. Our exit handler will decrement a depth counter, write some text to the log file, and jump to the original return address. To understand how we trace back the stack to find return addresses, we need to know exactly how Think C handles stack frames.

Stack Frames

Before and during function execution, space must be allocated for the following items:

• The function’s parameters

• The caller’s return address

• The function’s local variables

• Additional information, such as register contents, that the function may want to store

The first two items, the parameters and return address, are placed on the program stack by the calling code. Space for the the local variables and register storage is also allocated on the stack, but by the function itself. For convenience, the compiler uses register A6 to reference local variables while the stack pointer itself can be lowered and raised during function execution. The previous value of A6 is also placed on the stack so the compiler can easily clean up the stack when a function exits.

If FuncA calls FuncB, and FuncB calls FuncC, the stack looks like that shown in Figure 1.

As you can see, register A6 always points to the start of a linked list of previous A6 values. This is how debuggers such as MacsBug can back-trace function calls (using the SC command). In the _profile_ routine, we need to find the return address of the function that called the function that called us. The assembly language code finds this value on the stack at 4 + the previous A6 value. We save the old return address in a global array before modifying the stack so we know where to return to when our exit handler is called.

Note: If Think C’s force stack frame option is not active, the compiler doesn’t generate a stack frame for functions that have no local variables or parameters. Our _profile_ code is not called for these functions.

Sample Output

The code shown below produces the very simple log file also shown below. Note that the recursion in Func1 works properly. The braces in the output allow you to select an entire function using Think C’s Balance command.

/* 5 */

void DoSomething( void )
{
 Func1();
 Func2( 10 );
}

void Func1( void )
{
 static short  x = 0;
 if ( ++x < 2 )
 Func1();
}

short Func2( short x )
{
 return( 2 * x );
}

Here is the sample output from the code:

/* 6 */

DoSomething
{
 Func1
 {
 Func1 {}
 }
 Func2 {}
}

A simple object-oriented example produces the following output. Note how easy it is to follow the calling sequence of the constructors and destructors for both a base class and a child class.

/* 7 */

DoSomeOopStuff
{
 BaseClass::BaseClass {}
 ChildClass::ChildClass {}
 ChildClass::MiscFunc
 {
 BaseClass::MiscFunc {}
 }
 ChildClass::~ChildClass {}
 BaseClass::~BaseClass {}
}

Summary

A fairly simple technique was given to log function names to a text file for any Think C project, including object-oriented ones. The technique can be used to debug and optimize programs as well as to investigate a program’s runtime activity.

Possible future additions include:

• Put more information into the log file, such as the stack and register contents.

• Make the output look better, perhaps by drawing a graph of the program’s runtime activity.

• Do some validity checking on the heap and file id to make sure that the system is in a reasonably safe state for writing.

• Optionally log information to MacsBug using DebugStr() instead of to the log file.

• Support for interrupt-driven code and trap patches

This would involve setting some semaphores, restoring the global variable context, and changing the I/O calls to be asynchronous. I don’t think it would be very difficult, but as most Mac programmers know, nothing is difficult until you have to implement it.

Good luck, and let me know if you find any bugs.

Listing LogToFile.c
/*
 LogToFile.c
 © 1992 Rock Ridge Enterprises. All Rights Reserved.

 Requires Think C 5.0x

 To use this file:
 1a) Turn on the profiling and stack frame options for your    
 entire project from the Edit/Options/Debugging dialog.
 
 1b) Or, if you prefer, add the following line to your files:
 #pragma options( profile, force_frame )
 Place it within a function to profile just that function,
 within a file for just that file, or in a header file.

 2)Call LogInit at program initialization. For example:
 LogInit( NULL, true, false, true );
 
 3)Call LogDInit at program de-initialization. For example:
 LogDInit();

 4)You can call SetLogState( true ) or SetLogState( false )
 to turn logging on and off dynamically.
*/

#include <string.h>
#include <files.h>
#include <errors.h>
#include <memory.h>
#include <pascal.h>

#include “LogToFile.h”

#define kMaxLogDepth 100  // maximum 100 calls deep

 // create Think C text files as output
#define kThinkCreatorID   ‘KAHL’
#define kTextFileType‘TEXT’

 // strings written to output file
#define kTabString ((void*) “\t” )
#define kReturnString((void*) “\r” )
#define kOpenBraceString  ((void*) “{“)
#define kCloseBraceString ((void*) “}”)
// exiting a function that called nobody
#define kSimpleExitString “ {}”  

 // write this string the top of every log file
#define kStringForNewFile ((void*) “” )

 // write this string between program runs when appending to
 // the log file
#define kStringForReusedFile((void*)
 “\r\r*****************************\r”)

 // the largest buffer we’ll need (+ a little extra)
#define kMaxStringLength  ( kMaxLogDepth + 100 )

 // the default output file is on the root of the boot disk
#define kBootVol -1
#define kRootDir 2L
#define kDefaultPName“\PLog File.txt”

 // don’t profile our profile handler
#pragma options( !profile )

/*
 Permanent storage for this file
*/
static short   gLogFileID = 0;
// vRefNum of log file’s disk
static shortgLogFileVol = -1; 
// true = call FlushVol after every write
static Boolean   gAlwaysFlush = false; 
// true = logging is active
static Boolean   gLogActive = false; 
static FSSpec  gDefaultFileLoc = { kBootVol, kRootDir,
 kDefaultPName };

/*
 Info on the calling chain
*/
// how many calls deep are we?
static long gDepth = 0;   
// the return addresses
static void *gStack[ kMaxLogDepth ]; 
// are braces needed for this function?
static Boolean   gNeedBraces[ kMaxLogDepth ];

/*
 Internal routine prototypes
*/
void    _profile_( void *pFuncName );
void    StringPtoC( void *source, void *target );
OSErr   WriteOpenBrace( short howDeep );
OSErr   WriteFunctionEntry( void *pString );
OSErr   WriteFunctionExit( void );
OSErr   WriteOpenBrace( short howDeep );

/**********************************
 LogInit - Call at program start
 fileLoc- set to NULL or a valid FSSpec for the                
 output file
 deleteOld- true => truncate old log file
 alwaysFlush- true => call FlushVol a lot (better log          
  file if you crash)
 startLogging  - true => turn logging on, false => don’t       
  log yet
**********************************/
OSErr LogInit( FSSpec *fileLoc, Boolean deleteOld,
 Boolean alwaysFlush, Boolean startLogging )
{
 OSErr  err = noErr;
 BooleancreatedFile = false;
 
 if ( !fileLoc )
 // use default if user doesn’t specify one
 fileLoc = &gDefaultFileLoc;

 // in case user calls init twice
 if ( !gLogFileID )
 {
 /*
 Create the file & open the data fork for writing.
 */
 err = FSpCreate( fileLoc, kThinkCreatorID,
 kTextFileType, 0 );
 if ( !err )
 createdFile = true;
 
 err = FSpOpenDF( fileLoc, fsRdWrPerm, &gLogFileID );
 if ( err ) goto DONE;
 }

 /*
 Clear out the file if the user requests it.
 */
 if ( deleteOld )
 {
 err = SetEOF( gLogFileID, 0L );
 if ( err ) goto DONE;
 }

 /*
 Append to the file
 */
 err = SetFPos( gLogFileID, fsFromLEOF, 0 );
 if ( err ) goto DONE;

 /*
 Setup the globals and write ‘****’ to the file.
 */
 gAlwaysFlush = alwaysFlush;
 gLogActive = startLogging;
 gLogFileVol = fileLoc->vRefNum;
 
 // write a header to the file
 if ( deleteOld || createdFile )
 err = WriteLogString( kStringForNewFile );
 else
 err = WriteLogString( kStringForReusedFile );
 
 DONE:
 if ( err )
 LogDInit();

 return( err );
}

/**********************************
 LogDInit - Call at program exit
**********************************/
OSErr LogDInit( void )
{
 OSErr  err;

 if ( !gLogFileID )
 return( openErr );
 
 /*
 Close the file and flush the data to the disk.
 */
 err = FSClose( gLogFileID );
 if ( !err )
 err = FlushVol( NULL, gLogFileVol );
 
 /*
 Clear out the globals so we know we’re not active.
 */
 gLogFileID = 0;
 gLogActive = false;

 return( err );
}

/**********************************
 SetLogState - Call to start or restart logging. 
 Returns previous state.
**********************************/
Boolean SetLogState( Boolean startLogging )
{
 Booleanresult;
 
 result = gLogActive;
 gLogActive = startLogging;

 return( result );
}

/**********************************
 SetLogFlush - Call to start or restart flushing. 
 Returns previous state.
**********************************/
Boolean SetLogFlush( Boolean startFlushing )
{
 Booleanresult;
 
 result = gAlwaysFlush;
 gAlwaysFlush = startFlushing;

 return( result );
}

/**********************************
 ClearLogFile - Call to zero out the log file
**********************************/
OSErr ClearLogFile( void )
{
 OSErr  err = noErr;
 OSErr  err2;
 
 if ( !gLogFileID )
 return( openErr );
 
 err = SetEOF( gLogFileID, 0L );

 if ( gAlwaysFlush )
 {
 err2 = FlushVol( NULL, gLogFileVol );
 if ( !err )
 err = err2;// return the first error to occur
 }

 return( err );
}

/**********************************
 WriteLogString - Write a C string to the log file
**********************************/
OSErr WriteLogString( void *cString )
{
 OSErr  err = noErr;
 OSErr  err2;
 long   numBytes;
 
 if ( !gLogFileID )
 return( openErr );

 /*
 Write the data to the file
 */
 numBytes = strlen( cString );
 err = FSWrite( gLogFileID, &numBytes, cString );
 
 /*
 Flush the volume if we always flush
 */
 if ( gAlwaysFlush )
 {
 err2 = FlushVol( NULL, gLogFileVol );
 if ( !err )
 err = err2;
 }

 return( err );
}

/**********************************
 StringPtoC - Convert a pascal string to a c string
**********************************/
static void StringPtoC( void *source, void *target )
{
 BlockMove( source, target, 1 + *( (unsigned char*)source ));
 PtoCstr( target );
}

/**********************************
 WriteFunctionEntry - called by _profile_ whenever a function  is entered

 The following string is written to the output:
 <CR> + <TABS> + FunctionName
 Where <CR> is a carriage return and <TABS> indicates 1        
 tab per depth.
**********************************/
static OSErr WriteFunctionEntry( void *pString )
{
 Str255 cString;
 unsigned char   theString[ kMaxStringLength ];
 long   count;
 OSErr  err;

 // convert func name to c string
 StringPtoC( pString, cString );   

 // start with a carriage return
 strcpy( (void*)theString, kReturnString );  
 
 // 1 tab for each level
 for ( count=0; count<gDepth; count++ )
 strcat( (void*)theString, kTabString );
 
 // the function name
 strcat( (void*)theString, (void*)cString );

 // write the string
 err = WriteLogString( theString );
 return( err );
}

/**********************************
 WriteFunctionExit - called whenever a function is exited
 by our exit handler

 If this function called another function, write the
 following string:
 <CR> + <TABS> + }
 Otherwise, write:
 {}
 Where <CR> is a carriage return and <TABS> indicates 1
 tab per depth.
**********************************/
static OSErr WriteFunctionExit( void )
{
 OSErr  err = noErr;
 long   count;
 unsigned char   theString[ kMaxStringLength ];
 
 if ( gNeedBraces[ gDepth ] )
 {
 // start with a carriage return
 strcpy( (void*)theString, kReturnString );
 // indent 1 tab for each level
 for ( count=0; count<gDepth; count++ )
 strcat( (void*)theString, kTabString );
 // then a close-brace
 strcat( (void*)theString, kCloseBraceString );
 }
 else
 {
 // just write “exit”
 strcpy( (void*)theString, kSimpleExitString );
 }

// write the string
 err = WriteLogString( theString );
 return( err );
}

/**********************************
 WriteOpenBrace - adds some tabs and an open brace to the
 output

 The following string is written to the output:
 <CR> + <TABS> + {
 Where <CR> is a carriage return and <TABS> indicates 1
 tab per depth.
**********************************/
static OSErr WriteOpenBrace( short howDeep )
{
 OSErr  err;
 unsigned char   theString[ kMaxStringLength ];
 
 // start with a return
 strcpy( (void*)theString, kReturnString );  
 // 1 tab per level deep
 while( howDeep- > 0 )
 strcat( (void*)theString, kTabString );
 // add an open-brace
 strcat( (void*)theString, kOpenBraceString );

 err = WriteLogString( theString );
 return( err );
}

/**********************************
 _profile_ - Called every time a function is entered
 
 This more complicated version does the following:
 1) Prints the function name to the file in
    an indented list
 2) Saves the return address of the caller’s
    caller into gStack[]
 3) Modifies the stack so that the caller returns
    to our code and not to its caller.
 4) Prints exit info when the function is exited and
    then jumps to the correct return address.
**********************************/
void _profile_( void *pFuncName )
{
 OSErr  err;

 if ( !gLogFileID ) return; // output file not opened
 if ( !gLogActive ) return; // logging is off
 if ( gDepth >= kMaxLogDepth ) return; // we’re too deep

 /*
 We have to put an open brace in the output if the parent      
 function hasn’t called any other functions until now.
 */
 if ( gDepth > 0 )
 if ( !gNeedBraces[gDepth-1] )
 {
 gNeedBraces[gDepth-1] = true;
 err = WriteOpenBrace( gDepth-1 );
 if ( err ) return;
 }

 // write the function name
 err = WriteFunctionEntry( pFuncName );
 if ( err ) return;

 gNeedBraces[ gDepth ] = false;
 

 /*
 Save the return address that the caller will return to.
 Modify the stack so that the caller will return to us         
 instead.
 */
 asm
 {
 ; gStack[ gDepth ] = return address where caller
 ; will return to

 ; A1 = &gStack[ gDepth ]
 lea.l  gStack, A1
 move.l gDepth, D0
 lsl.l  #2, D0
 adda.l D0, A1
 
 move.l (A6), A0 ; A0 = A6 from previous call
 move.l 4(A0), (A1); gStack[ gDepth ] = ret Addr
 
 ; Change the return address on the stack to
 ; point to our code
 lea    @FuncExit, A1
 move.l A1, 4(A0)

 addq.l #1, gDepth ; we’re one level deeper now
 
 ; return to caller
 unlk   A6
 rts
 }

 /*
 This code is executed when a profiled function exits
 */
 FuncExit:
 asm
 {
 move.l D0, -(SP); save return value onto stack
 subq.l #1, gDepth ; we’re one level more shallow

 ; write exit info to the file
 jsr    WriteFunctionExit

 ; get the real return address from our array
 ; and jump to it
 
 ; A0 = &gStack[ gDepth ]
 lea.l  gStack, A0
 move.l gDepth, D0
 lsl.l  #2, D0
 adda.l D0, A0
 
 move.l (SP)+, D0; restore return value
 move.l (A0), A0 ; A0=real return address
 jmp    (A0); jump to real return address
 }
}
 

Community Search:
MacTech Search:

Software Updates via MacUpdate

FileMaker Pro 19.4.2 - Quickly build cus...
FileMaker Pro is the tool you use to create a custom app. You also use FileMaker Pro to access your app on a computer. Start by importing data from a spreadsheet or using a built-in Starter app to... Read more
Adobe Illustrator 26.0.3 - Professional...
You can download Adobe Illustrator for Mac as a part of Creative Cloud for only $20.99/month. Adobe Illustrator for Mac is the vector graphics classics in the design industry. It is a digital... Read more
WhatRoute 2.4.9 - Geographically trace o...
WhatRoute is designed to find the names of all the routers an IP packet passes through on its way from your Mac to a destination host. It also measures the round-trip time from your Mac to the router... Read more
Notion 2.0.20 - A unified workspace for...
Notion is the unified workspace for modern teams. Notion Features: Integration with Slack Documents Wikis Tasks Release notes were unavailable when this listing was updated. Download Now]]> Read more
Monterey Cache Cleaner 17.0.2 - Clear ca...
Monterey Cache Cleaner is an award-winning general-purpose tool for macOS X. MCC makes system maintenance simple with an easy point-and-click interface to many macOS X functions. Novice and expert... Read more
Firetask Pro 4.6.8 - Innovative task man...
Firetask Pro represents the next generation of easy-to-use, project-oriented task management apps. By combining David Allen's powerful Getting Things Done (GTD®) approach with classical task... Read more
Smultron 13.0.4 - Easy-to-use, powerful...
Smultron 13 is the text editor for all of us. Smultron is powerful and confident without being complicated. Its elegance and simplicity helps everyone being creative and to write and edit all sorts... Read more
Box Sync 4.0.8057 - Online synchronizati...
Box Sync gives you a hard-drive in the Cloud for online storage. Note: You must first sign up to use Box. What if the files you need are on your laptop -- but you're on the road with your iPhone? No... Read more
Audio Hijack 3.8.10 - Record and enhance...
Audio Hijack (was Audio Hijack Pro) drastically changes the way you use audio on your computer, giving you the freedom to listen to audio when you want and how you want. Record and enhance any audio... Read more
Direct Mail 6.0.1 - Create and send grea...
Direct Mail is an easy-to-use, fully-featured email marketing app purpose-built for macOS. Create, send, and track great looking email campaigns that get results. Start your newsletter by selecting... Read more

Latest Forum Discussions

See All

Hopefully Not Jared’s Last Show – The To...
My suspicions from last week were correct, and after my two kids tested positive for Covid last week both my wife and I have now tested positive as well. It seems you just can’t escape this stuff lately. Thankfully the two little ones are pretty... | Read more »
TouchArcade Game of the Week: ‘Micro RPG...
I feel like idle games are one of those perfect fits for the mobile platform. Not that they replace more involved gaming experiences when you’re in the mood for that, but they do fit in alongside other types of games just fine as a “go to" when you... | Read more »
‘Phantom Blade: Executioners’ Closed Bet...
Phantom Blade: Executioners is holding a small-scale technical test that lets players get first dibs on the KungFuPunk action RPG. Offered to selected players only, S-Game’s first Closed Beta Test will provide players with limited edition in-game... | Read more »
New ‘Warhammer 40,000: Tacticus’ Video S...
Back in September Snowprint Studios, who you may know from their previous Legend of Solgard or Rivengard, announced that they’d partnered up with Games Workshop to put out a new tactical game in the Warhammer 40,000 universe titled Warhammer 40,000... | Read more »
SwitchArcade Round-Up: ‘Pokemon Legends:...
Hello gentle readers, and welcome to the SwitchArcade Round-Up for January 28th, 2022. We’ve got a bunch of new releases to look at today, with a few big hitters, a few mid-level diversions, and a healthy supply of compost. Since it’s Friday, we... | Read more »
Phantom Blade: Executioners, S-Game...
S-Game has kicked off its first Closed Beta Test for Phantom Blade: Executioners, inviting a selected few to get first dibs on the upcoming KungFuPunk action RPG on mobile. The CBT officially begins this January 28th, and beta testers will receive... | Read more »
‘Infinite Galaxy’ First Anniversary: Cel...
Cultivating a new generation of valiant commanders across 240 countries worldwide, Infinite Galaxy has quenched players’ thirst to explore the vastness of space – and there are only more intergalactic adventures to embark on from here on out. Camel... | Read more »
War and Order: How to brave the cold in...
War and Order's 6th-anniversary celebrations are underway, and all in good time too - this season not only brings about fabulous festivities, but it also lets players experience the harsh winter in an entirely new way. [Read more] | Read more »
‘Hidden Folks+’ Is This Week’s New Apple...
The original Hidden Folks from Adriaan de Jongh is an excellent hidden objects game featuring hand drawn visuals. It is an absolute joy to play, and it has now released on Apple Arcade in the form of Hidden Folks+ () as an App Store great. If you’... | Read more »
Mini Metro’s First Big Update of 2022 Ad...
Last year saw great updates for Dinosaur Polo Club’s Mini Metro ($3.99) which is also available on Apple Arcade as an App Store Great. | Read more »

Price Scanner via MacPrices.net

Apple has clearance 2020 13″ MacBook Airs ava...
Apple has clearance, Certified Refurbished, 2020 13″ Intel-based MacBook Airs in stock today starting at only $719 and up to $370 off original MSRP. Each MacBook features a new outer case, comes with... Read more
The cheapest iPhones for sale today at Apple...
Apple has restocked Apple Certified Refurbished iPhone 8 models starting at only $359. Each refurbished iPhone comes with a fresh external case, standard Apple 1-year warranty, and free shipping.... Read more
14″ MacBook Pro with Apple M1 Max CPU now in...
Looking for a new 14″ MacBook Pro with an Apple M1 Max CPU? Stock is finally trickling into Apple resellers. B&H has Silver 14″ M1 Max MacBook Pros in stock today for $2899 including free 1-2 day... Read more
14″ MacBook Pros with Apple M1 Pro CPUs are i...
Amazon is reporting stock of 14″ MacBook Pros with M1 Pro CPUs today with a $50 discount. Shipping is free, and delivery is available by February 1st for most configurations. Be sure to make your... Read more
Apple has restocked 13″ M1 MacBook Pros for $...
Apple has restocked a full line of 13″ M1 MacBook Pros available Certified Refurbished, starting at only $1099 and up to $230 off original MSRP. These are the cheapest M1 MacBook Pros for sale today... Read more
Apple’s AirPods Max headphones are on sale fo...
Amazon has Silver, Blue, and Space Gray Apple AirPods Max headphones on sale today for $100 off MSRP. Shipping is free, and all models are in stock today. Their price is the lowest currently... Read more
Open a new line of service at Verizon and get...
Verizon is giving away 64GB Apple iPhone 12 minis or your choice of an iPhone 11 to customers who choose one of these phones and open a new line of service. Offer is available online only, and no... Read more
Open-box 13″ M1 MacBook Airs now available st...
QuickShip Electronics has open-box return 13″ M1 MacBook Airs in stock and on sale for $200-$400 off MSRP on their eBay store right now with free express delivery. According to QuickShip, “The item... Read more
Verizon’s 2022 iPad promo: $100-$310 off any...
Verizon has cellular-capable iPads on sale for $100-$310 off MSRP when purchased with an Unlimited service plan. Sale price is applied to your account monthly over a 24 or 30 month period, depending... Read more
Sunday Sale: Apple AirPods are on sale for up...
Amazon has Apple AirPods on sale for $10-$100 off MSRP today, depending on the model. All are in stock today with free delivery: – AirPods Max headphones (Blue): $449 $100 off MSRP – AirPods Max... Read more

Jobs Board

Registered Nurse (RN) Employee Health PSJH -...
…is calling for a Registered Nurse (RN) Employee Health PSJH to our location in Apple Valley, CA.** We are seeking a Registered Nurse (RN) Employee Health PSJH to be Read more
Systems Administrator - Pearson (United State...
…and troubleshoot Windows operating systems (workstation and server), laptop computers, Apple iPads, Chromebooks and printers** + **Administer and troubleshoot all Read more
IT Assistant Level 1- IT Desktop Support Anal...
…providing tier-1 or better IT help desk support in a large Windows and Apple environment * Experience using IT Service Desk Management Software * Knowledge of IT Read more
Human Resources Business Partner PSJH - Provi...
…**is calling a** **Human Resources Business Partner, PSJH** **to our location in Apple Valley, CA.** **Applicants that meet qualifications will receive a text with Read more
Manager Community Health Investment Programs...
…is calling a Manager Community Health Investment Programs PSJH to our location in Apple Valley, CA.** **Qualified candidates will be invited to do a self-paced video Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.