os161 / man / libc / execvp.html
execvp.html
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<title>execvp</title>
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<h2 align=center>execvp</h2>
<h4 align=center>OS/161 Reference Manual</h4>

<h3>Name</h3>
<p>
execvp - execute a program found on the search path
</p>

<h3>Library</h3>
<p>
Standard C Library (libc, -lc)
</p>

<h3>Synopsis</h3>
<p>
<tt>#include &lt;unistd.h&gt;</tt><br>
<br>
<tt>int</tt><br>
<tt>execvp(const char *</tt><em>program</em><tt>,
char **</tt><em>args</em><tt>);</tt>
</p>

<h3>Description</h3>
<p>
<tt>execvp</tt> searches for <em>program</em> on the program search
path and execs it with <A HREF=../syscall/execv.html>execv</A> if
found. If <em>program</em> is not found or a serious error occurs, it
returns.
</p>

<p>
If <em>program</em> contains a slash, no search is done; the specified
string is passed directly to <tt>execv</tt>.
</p>

<p>
The <em>args</em> argument should be prepared exactly as for
<tt>execv</tt>.
</p>

<p>
The search path is a colon-delimited list of directories retrieved by
calling <A HREF=getenv.html>getenv</A> to retrieve the <tt>PATH</tt>
environment variable. Unless you implement <tt>execve</tt> and
environment variable passing, the value used is from a default
environment compiled into libc. This path searches the <tt>/bin</tt>,
<tt>/sbin</tt>, and <tt>/testbin</tt> directories.
</p>

<h3>Return Values</h3>
<p>
On success, <tt>execvp</tt> does not return; instead, the new program
begins executing. On failure, <tt>execvp</tt> returns -1, and sets
<A HREF=errno.html>errno</A> to a suitable error code for the error
condition encountered.
</p>

<h3>Errors</h3>
<p>
<tt>execvp</tt> can fail for any of the reasons <tt>execv</tt> can.
In addition, it produces ENOENT if the requested program is not
found.
</p>

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