Example:

    GTM>ZSTEP INTO:"W ! ZP @$ZPOS W !"
    

This ZSTEP resumes execution of the current routine. At the beginning of the next line executed, the ZSTEP action ZPRINTs the source code for that line. Because the specified action does not contain a BREAK command, execution continues to the next line and all subsequent lines in the program flow.

Example:

    GTM>S curx=$g(x),zact="ZST:curx=$g(x) I:zact B:curx'=$g(x)"
    GTM>ZSTEP INTO:zact
    

This sequence uses ZSTEP to invoke Direct Mode at the beginning of the first line after the line that alters the value of x.