Master the Mainframe Global User Group

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty

IEFBR14 is probably the most used program that doesn't do anything. If you're new to the Mainframe you'll soon be using it. The name of this program is derived from:

IEF - IBM department that wrote it
BR -  Assembler BRanch instruction
14 -  Register 14

So, all IEFBR14 does is a "BR 14". Well sort of.

When I started out in Mainframes one of the old lads (was probably only 45) in the team told me when IBM originally shipped IEFBR14 a bug was found in it.

Standard linkage is R14 contains address to return to and R15 contains the address of the called program. This meant, IEFBR14 returned a non-zero completion code (the value in R15).

So, a second version was shipped that cleared R15 before doing the "BR R14", resulting in the completion code being 0.

Whether or not this is true, I don't know. But, I find it funny that the smallest program in the world contained a bug.

You can look at IEFBR14 using ISRDDN . After starting ISRDDN input "mem IEFBR14". This returns the module address in storage. Tab to the box and hit enter:

 BROWSE IEFBR14&PLPA&Start:00E92000&Size:00000008 Line 00000000 Col 001 080
 Command ===> Scroll ===> CSR
********************************* Top of Data **********************************
 +0 (00E92000) 1BFF07FE 00000000 * ...Ú.... *
******************************** Bottom of Data ********************************

1BFF = SR 15,15 (sets completion code to zero)
07FF = BR 14

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty

Mainframe Trivia - let's try again


Well this has never happened before - no one entered last week's t-shirt challenge!  I asked for Mainframe Trivia and the only post was @Kathy Bazinet encouraging all of the mainframe musicians!  So since I can change the "rules" of this game whenever I want, I'm going to give Kathy a t-shirt just for being so nice!!

So let's try this trivia thing again.  This community has a mix of experienced mainframers and newcomers just learning.  I know you have some interesting tidbits to share with each other!  This is your chance to talk about how Fred Brooks didn't want to lead the System 360 project but ended up making it hugely successful.  Or why don't you tell us about why Column 72 means continue to the next line?  Why do mainframes use EBCDIC instead of ASCII?  I'm sure you have more.  Bring it!

The rules*:
1.  Every Thursday, I'll start a new discussion thread titled Weekly Challenge.

2.  This week, reply to the thread with your mainframe trivia.  

3.  Vote for your favorite entries by clicking the "Recommend" button next to your favorites.

4.  The following Thursday, I'll announce the winner and start the next week's thread.

5.  The person submitting the item with the most votes will receive one of these Legends of Z t-shirts (or equivalent)!

* The rules are not really rules.  This isn't a real contest or anything.  It's just something I feel like doing and having a fun excuse to share some cool t-shirts with you.  I hope you all have fun with it.  I am!

Misty