Eat spaces and newline (C)

• strcspn
• strspn
• Difference between CR LF, LF and CR line break types?

spn.c

#include <stdio.h>
#include <string.h>
 
 
int main(void)
{
    char buffer[15] = "Samaras\n";

    /* To remove the newline (LF or CR LF) at the end of the line */
    /* Note: this will put a null terminator at the 1st newline   */

    printf("Before: buffer=|%s|", buffer);
    /* Use of strcspn */
    /*/////////////////////////////////////////*/
    buffer[strcspn(buffer, "\r\n")] = '\0';
    /*/////////////////////////////////////////*/
    printf("After: buffer=|%s|", buffer);
    
    printf("\nSecond part\n");
    char* pointer = "  \tGeorge";
    /* If we have a pointer to the buffer (not the buffer itself) */
    /* to skip over leading whitespace                            */

    printf("Before: pointer=|%s|\n", pointer);
    /* Use of strspn. Different function from before! */
    /*/////////////////////////////////////////*/
    pointer += strspn(pointer, "\t\n\v\f\r ");
    /*/////////////////////////////////////////*/
    printf("After: pointer=|%s|\n", pointer);
   
    /* Now we will eat leading whitespaces and eat the first newline */
    printf("\nThird part\n");
    char line[35] = "    \t  I study in DIT\n";
    char* linePointer = line;
    size_t len;
    printf("Before: linePointer=|%s| and line=|%s|", linePointer, line);
    /*////////////////////////////////////////////////*/
    linePointer += strspn(linePointer, "\t\n\v\f\r ");
    len = strcspn(line, "\r\n");
    line[len] = '\0';
    /*////////////////////////////////////////////////*/
    printf("After: linePointer=|%s| and line=|%s|", linePointer, line);
    /* Which also gives you the length of the remaining part in len */
    printf("\nlen=%zu\n", len);
    printf("ENDofMAIN");
    return 0;
}

This code was developed by me, G. Samaras, but the idea was of the Nomimal Animal.

#include <stdio.h>
#include <string.h>
#include <ctype.h>

void trim (char *cs)
{
  char *p;
  size_t len = strlen(cs);
  for (p = cs + len - 1; isspace (*p); --p) /* nothing */ ;
  p[1] = '\0';
  for (p = cs; isspace (*p); ++p) /* nothing */ ;
  memmove (cs, p, len - (size_t) (p - cs) + 1);
}

void test ()
{
  char input[1000];
  printf ("Enter something: ");
  fgets (input, sizeof input, stdin);
  trim (input);
  printf ("|%s|\n", input);
}

int main()
{
  test();
  return 0;
}

This code was developed by Josh and I would like to personally thank him for sharing the code with us. He said: ” I didn’t like what you had, since it required knowing all of the whitespace characters, and my version really does overwrite them in the original memory space.”

Have questions about this code? Comments? Did you find a bug? Let me know! 😀
Page created by G. (George) Samaras (DIT)