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man_1_simple_shell
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man_1_simple_shell
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.TH HSH 1
.SH NAME
hsh \- Holberton Shell
.SH SYNOPSIS
.B hsh
[command] [options ...]
.SH COPYRIGHT
hsh \- is a holberton school first trimester project
.SH DESCRIPTION
.B hsh
is a shell command interpreter that executes command read from the standard input or from file.
.B hsh
is intend to be a clone of the standard command interpreter of
.B Unix
and
.B Unix-like
system.
.SH OPTIONS
A simple command is a sequence of optional variable assignments followed by blank-separated words and redirections,
and terminated by a control operator. The first word specifies the command to be
executed, and is passed as argument zero. The remaining words are passed as arguments to the invoked command.
.PP
The return value of a simple command is its exit status, or 128+n if the command is terminated by signal n.
.SS
Piplines
A pipeline is a sequence of one or more commands separated by one of the control operators | or |&. The format for a pipeline is:
.PP
[command [..ARGS]] [| - |&] [command2 [..ARGS]]
.PP
The standard output of command is connected via a pipe to the standard input of command2. This connection is performed before any redirections specified by the command (see REDIRECTION below). If
|& is used, command's standard error, in addition to its standard output, is connected to command2's standard input through the pipe; it is shorthand for 2>&1 |. This implicit redirection of the
standard error to the standard output is performed after any redirections specified by the command.
.SS Lists
A list is a sequence of one or more pipelines separated by one of the operators ;, &, &&, or ||, and optionally terminated by one of ;, &, or <newline>.
Of these list operators, && and || have equal precedence, followed by ; and &, which have equal precedence.
A sequence of one or more newlines may appear in a list instead of a semicolon to delimit commands.
.PP
If a command is terminated by the control operator &, the shell executes the command in the background in a subshell. The shell does not wait for the command to finish, and the return status is 0.
Commands separated by a ; are executed sequentially; the shell waits for each command to terminate in turn. The return status is the exit status of the last command executed.
AND and OR lists are sequences of one or more pipelines separated by the && and || control operators, respectively. AND and OR lists are executed with left associativity. An AND list has the form
.PP
command1 && command2
.PP
command2 is executed if, and only if, command1 returns an exit status of zero.
.PP
An OR list has the form:
.PP
command1 || command2
.PP
command2 is executed if and only if command1 returns a non-zero exit status. The return status of AND and OR lists is the exit status of the last command executed in the list.
.SH AUTHORS
Sebri Issam \- Holberton School Software Engineer Student
.SH VERSIONS
.B hsh
V1.0.0