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<p>imported material</p> <p><b>New page</b></p><div>&#039;&#039;&#039;Problem&#039;&#039;&#039;. Unix/Linux systems are heavily based in text files. In particular, a record in a Unix file is identified by a text line, which is a character sequence ending with LineFeed. We would like to read lines from a text file, for example a log file, what is the right way to do it? Consider always the log writing process can happen anytime, even when we are reading and we can&#039;t assume we have permission to lock the file when we are reading from it.<br /> <br /> &#039;&#039;&#039;Solution&#039;&#039;&#039;. In the week ending 22-Oct-2021 I [NM] tried to use the &lt;code&gt;StandardFileStream&gt;&gt;upTo:&lt;/code&gt; method. It was a disaster. This method does not do what we want out of the box and it is in the ANSI standard, it is not a good idea to change it. We added a new method to Cuis to cope with this task on 27-Oct. See &lt;code&gt;StandardFileStream&gt;&gt;upTo:delimiterIsTerminator:&lt;/code&gt;. When &lt;code&gt;delimiterIsTerminator&lt;/code&gt; is set to &lt;code&gt;true&lt;/code&gt; the method is perfect for reading log files and makes the task very easy and error free. Please see the test methods in package &lt;code&gt;BaseImageTests&lt;/code&gt; for further details and comments.<br /> <br /> &#039;&#039;&#039;Example-1&#039;&#039;&#039;<br /> &quot; . create a file near the Image for tests and put in a fist line &quot;<br /> fw _ &#039;tmp.txt&#039; asFileEntry . <br /> fw fileContents: &#039;line-1&#039;, (Character lf) asString . <br /> <br /> &quot;. open the reader stream and read up to when you find something &quot;<br /> rs _ &#039;tmp.txt&#039; asFileEntry readStream.<br /> rs upTo: (Character newLineCharacter) delimiterIsTerminator: true. &quot;=&gt; &#039;line-1<br /> &#039; &quot;<br /> rs upTo: (Character newLineCharacter) delimiterIsTerminator: true. &quot;=&gt; nil &quot;<br /> <br /> &quot;. add a line to the file &quot;<br /> fw appendContents: &#039;line-2&#039;, (Character lf) asString .<br /> <br /> &quot;. and you will get it in the reader stream &quot;<br /> rs upTo: (Character newLineCharacter) delimiterIsTerminator: true. &quot;=&gt; &#039;line-2<br /> &#039; &quot;<br /> <br /> &quot;. remember to close the stream &quot;<br /> rs close. <br /> ----Dr. Nicola Mingotti started this page on 22-Oct-2021. Last updated 27-Oct-2021.</div>

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