z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

v If –S is not specified, the shell searches for the file in the current working
directory, then in PATH. The file must have read access permitted for the user.
Executable access permission is not necessary.
In addition to these options, you can use any valid option to the set command
(including –o option) as a command-line option to sh. See set for details.
Command Syntax
The shell implements a sophisticated programming language that gives you
complete control over the execution and combination of individual commands.
When the shell scans its input, it always treats the following characters specially:
; & ( ) < > | ’ \ "
space tab newline
If you want to use any of these characters inside an actual argument, you must
quote the argument (so that the shell does not use the special meanings of the
characters). See “Quoting” on page 558 for more information.
A simple command is a list of arguments separated by characters in the IFS
environment variable (the default value of IFS has blank, tabs, and newlines).
When a word is preceded by an unescaped pound sign (#), the remainder of the
line is treated as a comment, and the shell discards input up to but not including the
next newline. When a command starts with a defined alias, sh replaces the alias
with its definition (see alias).
A reserved-word command starts with a reserved word (for example, if, while, or
for). Reserved-word commands provide flow of control operations for the shell.
These are described in “Reserved-Word Commands” on page 552.
A command can be any of the following:
command:
simple command
reserved-word command
(command)
command |command
command &&command
command ||command
command &command
command &
command |&
command ;command
command ;
command
The following is the order of precedence of the preceding operators. The highest
priority operators are listed first, and operators on the same line have equal priority.
()
|
&& ||
& |& ;
The meaning of these operations is as follows:
(command)
Runs command in a child shell. The current shell invokes a second shell,
sh
Chapter 2. Shell command descriptions 551