It's been 35 years :) It might even have been a packed field. But it did loop because the negative representation of zero did not match the zero the code was looping unitl :)
> -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] > On Behalf Of John McKown > Sent: Wednesday, September 14, 2016 1:00 PM > To: [email protected] > Subject: Re: Bypassing s322 > > On Wed, Sep 14, 2016 at 2:51 PM, Gibney, Dave <[email protected]> wrote: > > > Once, in my first months here, a program appeared to be looping, but > > maybe not. It was impacting the system, but I insisted it be allowed > > to run and it was for a while. > > It was a Cobol program. Perform until some COMP field reached zero. > > The Cobol of the time did not recognize negative zero (X'80000000') > > in a COMP field as zero. > > > > > ​Hum, x'80000000' in 2-complement binary is not -0, it is > -2,147,483,648 > ​ . ref: > https://urldefense.proofpoint.com/v2/url?u=https- > 3A__en.wikipedia.org_wiki_32- > 2Dbit&d=DQIFaQ&c=C3yme8gMkxg_ihJNXS06ZyWk4EJm8LdrrvxQb- > Je7sw&r=u9g8rUevBoyCPAdo5sWE9w&m=vyEGno2UwsNi3TyWCpgDmFCJ2r > oOpPY30QnpZVR9LCw&s=Ch2PMt6L1Xyzxt5izQlcs9D87adUiSxqt9pH- > GMLK9w&e= > ​ > ​ > > > > -- > Unix: Some say the learning curve is steep, but you only have to climb it > once. -- Karl Lehenbauer > Unicode: https://urldefense.proofpoint.com/v2/url?u=http- > 3A__xkcd.com_1726_&d=DQIFaQ&c=C3yme8gMkxg_ihJNXS06ZyWk4EJm8L > drrvxQb- > Je7sw&r=u9g8rUevBoyCPAdo5sWE9w&m=vyEGno2UwsNi3TyWCpgDmFCJ2r > oOpPY30QnpZVR9LCw&s=uulDZEnFlqF00D7MI1Lfc- > nYsxV9EQKC0VSYBXwe590&e= > > Maranatha! <>< > John McKown > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
