By OS/360 release 19 (1970) && was the documented way to specify a temporary data set. See page 168 of http://www.bitsavers.org/pdf/ibm/360/os/R19_Jun70/GC28-6704-0_JCL_Reference_Rel_19_Jun70.pdf
<quote> If you do include the DSNAME parameter, the temporary data set name can consist of 1 through 8 characters and is preceded by two ampersands (&&). The character following the ampersands must be an alphabetic or national (~r#,$) character: the remaining characters can be any alphameric or national characters. (A temporary data set name that is preceded by only one ampersand is treated as a temporary data set name as long as no value is assigned to it either on the EXEC statement for this job step when it calls a procedure, or on a PROC statement within the procedure. If a value is assigned to it by one of these means, it is treated as a symbolic parameter. </quote> There is no change bar on that paragraph, so it was likely introduced with an earlier release. I don't have access to an earlier JCL manual, other than the one from 1967 that Shmuel referenced. -- Tom Marchant On Thu, 6 Jul 2023 02:15:28 +0000, Seymour J Metz <sme...@gmu.edu> wrote: >In that era, double ampersand was invalid. When IBM added symbolic parameters, >they added double ampersand as an escape for a single ampersand. I don't know >whether they were thinking about temporary DSNs when they came up with the >rule. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
