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copied!<pre><code>long *readSeqFile(char *filename); </code></pre> <p>You might want to make <code>filename</code> const:</p> <pre><code>long *readFileName(const char *const filename); </code></pre> <p>UPDATE: while this answers the original question, it's not very good C practise. If, as the poster says, he wants to read a list of integers from a file and get it back as an array of long, then the prototype is probably going to look something like this:</p> <pre><code>int readSeqFile(const char *const filename,long **longArray,size_t *const len); </code></pre> <p>and the implementation (in sketch form):</p> <pre><code>#include <stdio.h> #include <stdlib.h> const size_t longArrayChunkSize=100; int readSeqFile(const char *const filename,long **longArray, size_t *const len) { FILE *fp; size_t nInts=0,curBufferLen; long tmp; fp=fopen(filename,"r"); if(fp==NULL) return -1; *longArray=malloc(longArrayChunkSize*sizeof(long)); if(*longArray==NULL) return -1; curBufferLen=longArrayChunkSize; // let's assume file is a list of integers, one per line while(read from file and !feof()) { (scan line into tmp) longArray[nInts++]=tmp; if(nInts==curBufferLen) (realloc *longArray by longArrayChunkSize, increase curBufferLen) } *len=nInts; fclose(fp); return 0; } </code></pre> <p>Call it like this: <code>result=readSeqFile(filename,&longArray,&arrayLen);</code> <code>longArray</code> is of type <code>long*</code> and it is the caller's responsibility to free it afterwards. The result is zero on success and -1 on error.</p> <p>This is where you win with C++ and STL classes like <code>vector<long></code> since you can just <code>push_back()</code> each long as it comes out of the file without having to worry about memeory management.</p>

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