When I was just hired, the project most people in the Uithoorn laboratory in the Netherlands were working on was the development and maintenance of DOS. Yes that means Disk Operating Systems and no, it was not the Microsoft system that ran on early PC’s. It ran on medium-range IBM mainframes, big blue boxes in air-conditioned rooms. There were two mainframes in the lab, the largest had a whopping main memory of 64K, nowadays hardly enough for a page of text.

I started to work on October 1st 1969, and there was a group of developers from the Endicott (NY) laboratory, with the purpose of transferring the development of DOS to our Uithoorn laboratory.

My colleagues in the test lab where I was located, were sent on a half-year education program in the US, but for me there was no time to do that. So, I did a self-study course where I learned that CPU meant Central Processing Unit and so on. Then I had to take a test, which happened to be in Dutch, therefore I had a hard time to figure out what CVE meant (Centrale Verwerkings Eenheid). When I passed the test, I was sent to a course about Assembler machine language for a week, in Amsterdam.

The Americans planned to stay for 2 years, but by the end of October it was decided that the transfer would be cancelled. Panic all over of course, and for me, it was not clear what I should be working on now.

They gave me a pile of punched cards. It was the output of  a test run of an optical character recognition machine that the hardware department was developing. The machine would be used to read money transfer cards from a large Dutch bank. As an aside: the knowledge about optical character recognition was very advanced in this hardware group. When IBM decided to stop this project in the Netherlands, it would take 15 years until comparable expertise was developed in the US.

This pile of cards I was given should be read and then 10 different tables of test results should be printed. Why don’t you program this in PL/I, I was told. PL/I was a structured programming language, very new at that time, where you could program at a more abstract level that shifting values in and out machine registers. I did some self-study again and started writing, 80 pages with 29 lines, of 80-column data entry forms. The data entry department punched it all in punch cards and I ran back and forth to the computer center to get the program compiled and running, which succeeded after a while, about 4 months after I started working.

What have I done wrong to get this? I thought, when they gave me an informal award for it. My manager said that they realized I was asked something impossible to do, which is not surprising when I read the text in the IBM local newspaper, saying that I wrote 100,000 lines of code in three months. This was the line count of the 200 page machine language compiler output that I printed once by accident. So much for the power of higher level programming in a language like PL/I!

About a year later DOS came back to the Uithoorn laboratory and I was sent with about 4 colleagues to Endicott, upstate New York, for 2 months (no, not 2 years) to get it. Now my department was in charge of testing the operating system. In order to do that we had a few large cabinets full of trays with punched cards containing test cases. For each test we had to make a selection of these test cases and then adapt this set to the particular computers and configuration this test set would be run on. This involved changing the punched cards to enter hardware addresses and to write out by hand what the test set would cover. Of course this was very tedious and our testing was not very sophisticated in ensuring coverage of all subjects and in many configurations.

Then, our computer center started offering services on CMS. I forgot what it stands for, but it was a time sharing system. I thought that this would be really nice to improve our testing process. I loaded all test cases onto a hard disk of this CMS system and I wrote some PL/I programs to allow selecting test cases according to a test matrix and adapting the hardware addresses according to the environment, outputting the whole test set on magnetic tape. It was a huge success and literally we threw away all punched cards. This was the end of the punched card era for us.


I will spare you the trouble I had with a manager who did not understand this and who said to me that it was unfair for me to earn the same amount as my male colleagues because I had a husband who earned money also. His manager, an American, understood very well what the impact was of what I had done and so it happened that while I was still depressed about the fight with my manager, I received an outstanding contribution award. This time I was very pleased.

Before you start wondering what this piece of text has to do with being female within IBM, bear with me a little more. Fast forward a few months, until October 6th, 1973. I was invited, together with Peter, to an outstanding award winners’ recognition event in the then just opened Selfridge hotel in London. Peter, my husband, was hesitant to go, because, as he said, he was afraid that he would be asked why he won the award (instead of me). Of course, that happened a few times.

We had a great weekend, with a theater show, a supper on the 2nd world war MS Belfast, and the event ended with a dinner for the about 100 attendees at the Selfridge hotel. The row of speakers was ended by a very important person within IBM. Maybe I should not mention his name.

He elaborated how important it was what the award winners had done for IBM and then he continued saying that he felt deeply for the poor wives waiting long evenings and weekends while their husbands were busy doing their award winning work! Peter started saying “Boohoo”, not so softly, and our lab director, also sitting at our table started hissing “Sshhh!”.

We really wondered whether that VIP was informed that (at least) one of the award winners was female.


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