Search code examples
cstrtok

Get one specific token of string in C

I have a file that has text inside it (<tab> is \t):

display <tab> output_stmt
[ <tab> left_bracket
"Hello World" <tab> string_const
] <tab> right_bracket
~ <tab> term_sym

How can I get the strings after the <tab>, skipping the first string and <tab> everyline.

I only know how to get only the first string and ignore the rest of the line by using: 

strtok(variablename, "\t");

Any useful answers are much appreciated.
Thank you!

Solution

  • With the strtok() function you can get also the next token. See the man page of strtok():

    The strtok() function breaks a string into a sequence of zero or more nonempty tokens. On the first call to strtok() the string to be parsed should be specified in str. In each subsequent call that should parse the same string, str must be NULL.

    So you can call:

    char* tokenOne = strtok(variablename, "\t"); /* first token  */
char* tokenTwo = strtok(NULL, "\t");         /* second token */

    Note that you don't have to free memory because strtok() works with the input buffer as it changes it e.g.:

    "display \t output_stmt\0"

    will be:

    "display \0 output_stmt\0"

    after the call of strtok(). After that it just returns a pointer to the next token.