The Source Integrity Professional Edition User Guide - MKS

Using the MKS Make Utility
Try some experiments on small makefiles, using make with the -v
option, to see suffix rules work.
More About Executing Recipes
Regular
Recipes
Note Because MKS Make searches met-rules first, you should specify
the -r option on the command line to disable the default met-rules when
experimenting with suffix rules.
To update a target, MKS Make expands and executes a recipe. The
expansion process replaces all macros and text diversions within the
recipe, then either executes the commands directly, or passes them to
a shell or command interpreter, depending on the occurrence of shell
metacharacters in the recipe.
When MKS Make calls a regular recipe, it executes each line of the
recipe separately. This means that the effect of some commands may
not carry over from one recipe line to the next.
For example, a change directory request (cd) in a recipe line changes
the current directory only for that recipe line. The next recipe line
reverts to the previous current directory.
The value of the control macro SHELLMETAS determines whether
MKS Make uses a shell to execute a command. If it finds any
character in SHELLMETAS in the expanded recipe line, it passes the
command to the shell for execution; otherwise, it executes the
command directly.
Note If the makefile contains the .POSIX special target, MKS Make
always uses the shell to execute recipe lines.
To force the use of a shell, you can add characters from SHELLMETAS to
the recipe line, as in the example
rule 1
# the next lines contains shell metacharacters
command_one > file_one
command_two | command_three
…
288 Source Integrity Professional Edition