| int strlen(s) | Returns the length of s |
| strcat(s1, s2) | String concatenation: appends s2 to s1 |
| strcmp(s1, s2) | Comparison: -1 if s1 < s2 0 if s1==s2 +1 if s1>s2 |
| strcpy(s1, s2) | Copies of the contents of s2 into s1 |
| strncpy(s1, s2, size) | Copies a maximum of n characters from s2 to s1. |
| strncat(s1, s2, size) | Concatinates a maximum of n characters from s2 to the end of s1. |
| strchr(s, c) | Returns a pointer to the first location of c in s; returns \0 (NULL) if not found |
| strstr(s1, s2) | Returns a pointer to the first location of s2 in s1; returns NULL if not found |
Any complex technology -- if sufficiently well developed and applied -- is to the ordinary public indistinguishable from magic.
Arthur C. Clarke.