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diff --git a/share/doc/gdb/system.html b/share/doc/gdb/system.html new file mode 100644 index 0000000..ab3f82e --- /dev/null +++ b/share/doc/gdb/system.html @@ -0,0 +1,135 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. Buying copies from GNU Press supports the FSF in +developing GNU and promoting software freedom." --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Debugging with GDB: system</title> + +<meta name="description" content="Debugging with GDB: system"> +<meta name="keywords" content="Debugging with GDB: system"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="List-of-Supported-Calls.html#List-of-Supported-Calls" rel="up" title="List of Supported Calls"> +<link href="Protocol_002dspecific-Representation-of-Datatypes.html#Protocol_002dspecific-Representation-of-Datatypes" rel="next" title="Protocol-specific Representation of Datatypes"> +<link href="isatty.html#isatty" rel="previous" title="isatty"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="system"></a> +<div class="header"> +<p> +Previous: <a href="isatty.html#isatty" accesskey="p" rel="previous">isatty</a>, Up: <a href="List-of-Supported-Calls.html#List-of-Supported-Calls" accesskey="u" rel="up">List of Supported Calls</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="system-1"></a> +<h4 class="unnumberedsubsubsec">system</h4> +<a name="index-system_002c-file_002di_002fo-system-call"></a> + +<dl compact="compact"> +<dt>Synopsis:</dt> +<dd><div class="smallexample"> +<pre class="smallexample">int system(const char *command); +</pre></div> + +</dd> +<dt>Request:</dt> +<dd><p>‘<samp>Fsystem,<var>commandptr</var>/<var>len</var></samp>’ +</p> +</dd> +<dt>Return value:</dt> +<dd><p>If <var>len</var> is zero, the return value indicates whether a shell is +available. A zero return value indicates a shell is not available. +For non-zero <var>len</var>, the value returned is -1 on error and the +return status of the command otherwise. Only the exit status of the +command is returned, which is extracted from the host’s <code>system</code> +return value by calling <code>WEXITSTATUS(retval)</code>. In case +<samp>/bin/sh</samp> could not be executed, 127 is returned. +</p> +</dd> +<dt>Errors:</dt> +<dd> +<dl compact="compact"> +<dt><code>EINTR</code></dt> +<dd><p>The call was interrupted by the user. +</p></dd> +</dl> + +</dd> +</dl> + +<p><small>GDB</small> takes over the full task of calling the necessary host calls +to perform the <code>system</code> call. The return value of <code>system</code> on +the host is simplified before it’s returned +to the target. Any termination signal information from the child process +is discarded, and the return value consists +entirely of the exit status of the called command. +</p> +<p>Due to security concerns, the <code>system</code> call is by default refused +by <small>GDB</small>. The user has to allow this call explicitly with the +<code>set remote system-call-allowed 1</code> command. +</p> +<dl compact="compact"> +<dt><code>set remote system-call-allowed</code></dt> +<dd><a name="index-set-remote-system_002dcall_002dallowed"></a> +<p>Control whether to allow the <code>system</code> calls in the File I/O +protocol for the remote target. The default is zero (disabled). +</p> +</dd> +<dt><code>show remote system-call-allowed</code></dt> +<dd><a name="index-show-remote-system_002dcall_002dallowed"></a> +<p>Show whether the <code>system</code> calls are allowed in the File I/O +protocol. +</p></dd> +</dl> + + + + +</body> +</html> |