How can I get a string from input without including a newline using fgets? [duplicate]

Question

I'm trying to write an inputted string elsewhere and do not know how to do away with the new line that appears as part of this string that I acquire with stdin and fgets.

 char buffer[100]; memset(buffer, 0, 100); fgets(buffer, 100, stdin); printf("buffer is: %s\n stop",buffer);

I tried to limit the amount of data that fgets gets as well as limiting how much of the data is written but the new line remains. How can I simply get the inputted string up to the last character written with nothing else?

@BLUEPIXY scanf("%99[^\n]%*c", buffer) will not read anything into buffer if the first char is '\n'. The '\n' remains in stdin. — chux
– chux, Commented Dec 15, 2014 at 20:07
Do you want to read a line and leave the '\n' in the input stream, or do you want to read a line including the '\n' and then discard the '\n'? (This will affect the next input operation, which will or will not see the '\n' waiting for it.) — Keith Thompson
– Keith Thompson, Commented Dec 15, 2014 at 20:13

madz · Accepted Answer · 2014-12-15 18:59:07Z

5

try

fgets(buffer, 100, stdin); size_t ln = strlen(buffer)-1; if (buffer[ln] == '\n') buffer[ln] = '\0';

answered Dec 15, 2014 at 18:59

madz

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Community · Accepted Answer · 2017-05-23 11:54:57Z

Simply look for the potential '\n'.

After calling fgets(), If '\n' exists, it will be the last char in the string (just before the '\0').

size_t len = strlen(buffer); if (len > 0 && buffer[len-1] == '\n') { buffer[--len] = '\0'; }

Sample usage

char buffer[100]; // memset(buffer, 0, 100); not needed if (fgets(buffer, sizeof buffer, stdin) == NULL) { // good to test fgets() result Handle_EOForIOerror(); } size_t len = strlen(buffer); if (len > 0 && buffer[len-1] == '\n') { buffer[--len] = '\0'; } printf("buffer is: %s\n stop",buffer);

Notes:

buffer[strlen(buffer)-1] is dangerous in rare occasions when the first char in buffer is a '\0' (embedded null character).

scanf("%99[^\n]%*c", buffer); is a problem if the first char is '\n', nothing is read and '\n' remains in stdin.

strlen() is fast as compared to other methods: https://codereview.stackexchange.com/a/67756/29485

Or roll your own code like gets_sz

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