This is PTeX, C Version 2.99 j1.7e p1.0.9F (preloaded format=jlplain 95.7.4)  14 MAR 1996 18:01
**&jlatex \nonstopmode\input{sub.tex}

! Emergency stop.
\@iinput #1->\@@input #1 
                         
<*> &jlatex \nonstopmode\input{sub.tex}
                                       
*** (job aborted, file error in nonstop mode)

 
Here is how much of TeX's memory you used:
 3 strings out of 4318
 17 string characters out of 62130
 25263 words of memory out of 262141
 2061 multiletter control sequences out of 9500
 23946 words of font info for 90 fonts, out of 72000 for 255
 14 hyphenation exceptions out of 607
 3i,0n,3p,1b,7s stack positions out of 300i,40n,60p,4096b,4000s
No pages of output.