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| author | rsc <devnull@localhost> | 2005-01-14 03:45:44 +0000 |
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| committer | rsc <devnull@localhost> | 2005-01-14 03:45:44 +0000 |
| commit | 78e51a8c6678b6e3dff3d619aa786669f531f4bc (patch) | |
| tree | 015e00fde4fc837fd31b705e18d17dc913829388 /man/man3/errstr.html | |
| parent | 2634795b5f0053bc0ff08e5d7bbc0eda8efea061 (diff) | |
| download | plan9port-78e51a8c6678b6e3dff3d619aa786669f531f4bc.tar.gz plan9port-78e51a8c6678b6e3dff3d619aa786669f531f4bc.tar.bz2 plan9port-78e51a8c6678b6e3dff3d619aa786669f531f4bc.zip | |
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diff --git a/man/man3/errstr.html b/man/man3/errstr.html new file mode 100644 index 00000000..547efc8d --- /dev/null +++ b/man/man3/errstr.html @@ -0,0 +1,121 @@ +<head> +<title>errstr(3) - Plan 9 from User Space</title> +<meta content="text/html; charset=utf-8" http-equiv=Content-Type> +</head> +<body bgcolor=#ffffff> +<table border=0 cellpadding=0 cellspacing=0 width=100%> +<tr height=10><td> +<tr><td width=20><td> +<tr><td width=20><td><b>ERRSTR(3)</b><td align=right><b>ERRSTR(3)</b> +<tr><td width=20><td colspan=2> + <br> +<p><font size=+1><b>NAME </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + errstr, rerrstr, werrstr – description of last system call error<br> + +</table> +<p><font size=+1><b>SYNOPSIS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>#include <u.h><br> + #include <libc.h> + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>int errstr(char *err, uint nerr) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>void rerrstr(char *err, uint nerr) + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + </font></tt> + <tt><font size=+1>void werrstr(char *fmt, ...)<br> + </font></tt> +</table> +<p><font size=+1><b>DESCRIPTION </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + When a system call fails it returns –1 and records a null terminated + string describing the error in a per-process buffer. <i>Errstr</i> swaps + the contents of that buffer with the contents of the array <i>err</i>. + <i>Errstr</i> will write at most <i>nerr</i> bytes into <i>err</i>; if the per-process + error string does not fit, it is silently truncated at a UTF + character boundary. The returned string is NUL-terminated. Usually + <i>errstr</i> will be called with an empty string, but the exchange property + provides a mechanism for libraries to set the return value for + the next call to <i>errstr</i>. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The per-process buffer is <tt><font size=+1>ERRMAX</font></tt> bytes long. Any error string + provided by the user will be truncated at <tt><font size=+1>ERRMAX−1</font></tt> bytes. <tt><font size=+1>ERRMAX</font></tt> + is defined in <tt><font size=+1><libc.h></font></tt>. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + If no system call has generated an error since the last call to + <i>errstr</i> with an empty string, the result is an empty string. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The verb <tt><font size=+1>r</font></tt> in <a href="../man3/print.html"><i>print</i>(3)</a> calls <i>errstr</i> and outputs the error string. + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Rerrstr</i> reads the error string but does not modify the per-process + buffer, so a subsequent <i>errstr</i> will recover the same string. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <i>Werrstr</i> takes a <i>print</i> style format as its argument and uses it + to format a string to pass to <i>errstr</i>. The string returned from + <i>errstr</i> is discarded. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + The error string is maintained in parallel with the Unix error + number <i>errno</i>. Changing <i>errno</i> will reset the error string, and + changing the error string via <i>errstr</i> or <i>werrstr</i> will reset <i>errno</i>.<br> + +</table> +<p><font size=+1><b>SOURCE </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>/usr/local/plan9/src/lib9/errstr.c<br> + </font></tt> +</table> +<p><font size=+1><b>DIAGNOSTICS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Errstr</i> always returns 0.<br> + +</table> +<p><font size=+1><b>SEE ALSO </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <a href="../man3/intro.html"><i>intro</i>(3)</a>, <a href="../man3/perror.html"><i>perror</i>(3)</a><br> + +</table> +<p><font size=+1><b>BUGS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + The implementation sets <i>errno</i> to the (somewhat arbitrary) constant + 0x19283745 when the error string is valid. When <i>errno</i> is set to + other values, the error string is synthesized using <a href="../man3/strerror.html"><i>strerror</i>(3)</a>.<br> + +</table> + +<td width=20> +<tr height=20><td> +</table> +<!-- TRAILER --> +<table border=0 cellpadding=0 cellspacing=0 width=100%> +<tr height=15><td width=10><td><td width=10> +<tr><td><td> +<center> +<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a> +</center> +</table> +<!-- TRAILER --> +</body></html> |