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This is probably a very newbish question, but can I fix this so that any characters (except \r) are added to my new string ucontents? Just now it only add characters up until the \r. I want to add characters after \r too. 

void to_unix_line_endings(char* contents, char* ucontents) { int i; for (i = 0; i < strlen(contents); i++) { if(contents[i] != '\r') { ucontents[i] = contents[i]; } } } char out[5000]; to_unix_line_endings("spaghettiand\rmeatballs", out); printf("%s\n", out); // Prints "spaghettiand". I want "spaghettiandmeatballs".

Thanks.

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    ucontents[i] : use other index variable instead of i. and null-terminator add to end. Commented May 8, 2016 at 13:42
  • Thanks. I've added how I fixed it below following your advice. Have I added the null terminator correctly? Commented May 8, 2016 at 13:48

2 Answers 2

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In the comments (under your answer), @BLUEPIXY is pointing out that because j will never be equal to length, ucontents will never be NULL terminated in the if(j == length) block.

So although your code example (in the answer section) appeared to work for you as is, the code will eventually fail. printf() needs a null terminator to identify end of string. When the memory you are writing to does not happen to have a NULL terminator in the right spot, it will fail. (as would any of the string functions).

The following change will null terminate your buffer:

void to_unix_line_endings(char* contents, char* ucontents) { int i; int j = 0; int length = strlen(contents);//BTW, good improvement over original post for (i = 0; i < length; i++) { if(contents[i] != '\r') { ucontents[j] = contents[i]; /*if (j == length) { //remove this section altogether ucontents[j] = '\0'; break; }*/ j++;//this increment ensures j is positioned //correctly for NULL termination when loop exits } } ucontents[j]=NULL;//add NULL at end of loop }
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Thanks. I changed my code to take out the redundant block.
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Fixed like so. Thanks, BLUEPIXY.

void to_unix_line_endings(char* contents, char* ucontents) { int i; int j = 0; int length = strlen(contents); for (i = 0; i < length; i++) { if(contents[i] != '\r') { ucontents[j] = contents[i]; if (j == length) { ucontents[j] = '\0'; break; } j++; } } }
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3 Comments

Thanks. That was better than what I did. I'm porting a program from C++ to C.
@SamSaint-Pettersen - Your if (j == length) block will never be executed. (this is what BLUEPIXY's comment is saying)
@ryyker: Thanks. I understood that. I meant the sample was better because it correctly attached the null character.

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