Set Char* to Trim of Char in C

Question

Lets see this example:

char var1[100] = "test    ";
char* var2;

If I do this:

var2 = &var1;

I'll get it with spaces.

I want var2 to be the trim of var1.

did you try anything? I suggest `strchr(var1, ' ')` as a good place to start — pm100, Nov 10 '16 at 16:57
`char var1 = "test ";` is not a valid initialization. You are attempting to assign an address (typically 4 or 8 bytes) value into a character (typically 1 byte) variable. — barak manos, Nov 10 '16 at 16:58
alternatively you can use a search engine , looking for 'c string trim' finds http://stackoverflow.com/questions/122616/how-do-i-trim-leading-trailing-whitespace-in-a-standard-way — pm100, Nov 10 '16 at 17:00
barak manos not its right. It was that way to make myself understood easily. sorry — Richasantos, Nov 10 '16 at 17:03

score 0 · Answer 1 · answered Nov 10 '16 at 17:01

As far as I know there's no way of doing this without changing the original string or copying a modified version of that string to a new source.

As pm100 said, you can find the pointer pointing to the first instance of space in that string, then get the distance from your source pointer and that pointer to find the index of the whitespace. After doing so, simply use strncpy to copy that portion of the string to a new pointer. Make sure you allocate your new pointer and put the terminating character '\0' at the end.

The other solution is to simply use strchr again as pm100 said, but this time change what that pointer points to to '\0'.

score 0 · Answer 2 · answered Nov 10 '16 at 17:03

0

a quicky

var2 = strdup(var1);
char * idx = strchr(var2, ' ');
if(idx) *idx = 0;

answered Nov 10 '16 at 17:03

pm100

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Set Char* to Trim of Char in C

2 Answers2