# C programming language C functions list The following C functions are available. ## In this section - [C string](https://d3codex.com/cfunctions/c-string/) - [CPSTR](https://d3codex.com/cfunctions/cpstr/) - [CPSTR*](https://d3codex.com/cfunctions/cpstr-asterisk/) - [_CP_alpha](https://d3codex.com/cfunctions/cp-alpha/) - [_CP_ascii](https://d3codex.com/cfunctions/cp-ascii/) - [_CP_at1](https://d3codex.com/cfunctions/cp-at1/) - [_CP_at2](https://d3codex.com/cfunctions/cp-at2/) - [_CP_atvar](https://d3codex.com/cfunctions/cp-atvar/) - [_CP_break](https://d3codex.com/cfunctions/cp-break/) - [_CP_build_msg](https://d3codex.com/cfunctions/cp-build-msg/) - [_CP_call](https://d3codex.com/cfunctions/cp-call/) - [_CP_casing](https://d3codex.com/cfunctions/cp-casing/) - [_CP_cat](https://d3codex.com/cfunctions/cp-cat/) - [_CP_clearfile](https://d3codex.com/cfunctions/cp-clearfile/) - [_CP_clearselect](https://d3codex.com/cfunctions/cp-clearselect/) - [_CP_close](https://d3codex.com/cfunctions/cp-close/) - [_CP_col1](https://d3codex.com/cfunctions/cp-col1/) - [_CP_col2](https://d3codex.com/cfunctions/cp-col2/) - [_CP_compare](https://d3codex.com/cfunctions/cp-compare/) - [_CP_convert](https://d3codex.com/cfunctions/cp-convert/) - [_CP_count](https://d3codex.com/cfunctions/cp-count/) - [_CP_crt](https://d3codex.com/cfunctions/cp-crt/) - [_CP_crt_n](https://d3codex.com/cfunctions/cp-crt-n/) - [_CP_data](https://d3codex.com/cfunctions/cp-data/) - [_CP_date](https://d3codex.com/cfunctions/cp-date/) - [_CP_dcount](https://d3codex.com/cfunctions/cp-dcount/) - [_CP_debug](https://d3codex.com/cfunctions/cp-debug/) - [_CP_delete](https://d3codex.com/cfunctions/cp-delete/) - [_CP_delete_item](https://d3codex.com/cfunctions/cp-delete-item/) - [_CP_dtx](https://d3codex.com/cfunctions/cp-dtx/) - [_CP_ebcdic](https://d3codex.com/cfunctions/cp-ebcdic/) - [_CP_echo](https://d3codex.com/cfunctions/cp-echo/) - [_CP_execute](https://d3codex.com/cfunctions/cp-execute/) - [_CP_extract](https://d3codex.com/cfunctions/cp-extract/) - [_CP_field](https://d3codex.com/cfunctions/cp-field/) - [_CP_field_store](https://d3codex.com/cfunctions/cp-field-store/) - [_CP_filelock](https://d3codex.com/cfunctions/cp-filelock/) - [_CP_fileunlock](https://d3codex.com/cfunctions/cp-fileunlock/) - [_CP_fold](https://d3codex.com/cfunctions/cp-fold/) - [_CP_footing](https://d3codex.com/cfunctions/cp-footing/) - [_CP_get](https://d3codex.com/cfunctions/cp-get/) - [_CP_heading](https://d3codex.com/cfunctions/cp-heading/) - [_CP_iconv](https://d3codex.com/cfunctions/cp-iconv/) - [_CP_in](https://d3codex.com/cfunctions/cp-in/) - [_CP_index](https://d3codex.com/cfunctions/cp-index/) - [_CP_input](https://d3codex.com/cfunctions/cp-input/) - [_CP_insert](https://d3codex.com/cfunctions/cp-insert/) - [_CP_interrupt](https://d3codex.com/cfunctions/cp-interrupt/) - [_CP_is_](https://d3codex.com/cfunctions/cp-is/) - [_CP_key](https://d3codex.com/cfunctions/cp-key/) - [_CP_load](https://d3codex.com/cfunctions/cp-load/) - [_CP_locate](https://d3codex.com/cfunctions/cp-locate/) - [_CP_lock](https://d3codex.com/cfunctions/cp-lock/) - [_CP_logon](https://d3codex.com/cfunctions/cp-logon/) - [_CP_match](https://d3codex.com/cfunctions/cp-match/) - [_CP_mkstr](https://d3codex.com/cfunctions/cp-mkstr/) - [_CP_mkstrl](https://d3codex.com/cfunctions/cp-mkstrl/) - [_CP_num](https://d3codex.com/cfunctions/cp-num/) - [_CP_occurs](https://d3codex.com/cfunctions/cp-occurs/) - [_CP_oconv](https://d3codex.com/cfunctions/cp-oconv/) - [_CP_open](https://d3codex.com/cfunctions/cp-open/) - [_CP_out](https://d3codex.com/cfunctions/cp-out/) - [_CP_out_msg](https://d3codex.com/cfunctions/cp-out-msg/) - [_CP_ovfly_subs](https://d3codex.com/cfunctions/cp-ovfly-subs/) - [_CP_page](https://d3codex.com/cfunctions/cp-page/) - [_CP_page_n](https://d3codex.com/cfunctions/cp-page-n/) - [_CP_pick_break](https://d3codex.com/cfunctions/cp-pick-break/) - [_CP_pick_env](https://d3codex.com/cfunctions/cp-pick-env/) - [_CP_precision](https://d3codex.com/cfunctions/cp-precision/) - [_CP_print](https://d3codex.com/cfunctions/cp-print/) - [_CP_print_n](https://d3codex.com/cfunctions/cp-print-n/) - [_CP_print_on](https://d3codex.com/cfunctions/cp-print-on/) - [_CP_printer](https://d3codex.com/cfunctions/cp-printer/) - [_CP_prompt](https://d3codex.com/cfunctions/cp-prompt/) - [_CP_read](https://d3codex.com/cfunctions/cp-read/) - [_CP_readfields](https://d3codex.com/cfunctions/cp-readfields/) - [_CP_readnext](https://d3codex.com/cfunctions/cp-readnext/) - [_CP_readt](https://d3codex.com/cfunctions/cp-readt/) - [_CP_readv](https://d3codex.com/cfunctions/cp-readv/) - [_CP_release](https://d3codex.com/cfunctions/cp-release/) - [_CP_release_all](https://d3codex.com/cfunctions/cp-release-all/) - [_CP_replace](https://d3codex.com/cfunctions/cp-replace/) - [_CP_replace_bridge](https://d3codex.com/cfunctions/cp-replace-bridge/) - [_CP_rewind](https://d3codex.com/cfunctions/cp-rewind/) - [_CP_root](https://d3codex.com/cfunctions/cp-root/) - [_CP_rs_](https://d3codex.com/cfunctions/cp-rs/) - [_CP_SADDR](https://d3codex.com/cfunctions/cp-saddr/) - [_CP_select](https://d3codex.com/cfunctions/cp-select/) - [_CP_send](https://d3codex.com/cfunctions/cp-send/) - [_CP_si_](https://d3codex.com/cfunctions/cp-si/) - [_CP_sleep](https://d3codex.com/cfunctions/cp-sleep/) - [_CP_SLEN](https://d3codex.com/cfunctions/cp-slen/) - [_CP_sort](https://d3codex.com/cfunctions/cp-sort/) - [_CP_soundex](https://d3codex.com/cfunctions/cp-soundex/) - [_CP_space](https://d3codex.com/cfunctions/cp-space/) - [_CP_sr_](https://d3codex.com/cfunctions/cp-sr/) - [_CP_str](https://d3codex.com/cfunctions/cp-str/) - [_CP_str_alloc](https://d3codex.com/cfunctions/cp-str-alloc/) - [_CP_str_copy](https://d3codex.com/cfunctions/cp-str-copy/) - [_CP_str_free](https://d3codex.com/cfunctions/cp-str-free/) - [_CP_str_null](https://d3codex.com/cfunctions/cp-str-null/) - [_CP_str_realloc](https://d3codex.com/cfunctions/cp-str-realloc/) - [_CP_str0](https://d3codex.com/cfunctions/cp-str0/) - [_CP_substr](https://d3codex.com/cfunctions/cp-substr/) - [_CP_sum](https://d3codex.com/cfunctions/cp-sum/) - [_CP_system](https://d3codex.com/cfunctions/cp-system/) - [_CP_TERM](https://d3codex.com/cfunctions/cp-term/) - [_CP_time](https://d3codex.com/cfunctions/cp-time/) - [_CP_timedate](https://d3codex.com/cfunctions/cp-timedate/) - [_CP_trans](https://d3codex.com/cfunctions/cp-trans/) - [_CP_trim](https://d3codex.com/cfunctions/cp-trim/) - [_CP_unix_break](https://d3codex.com/cfunctions/cp-unix-break/) - [_CP_unix_env](https://d3codex.com/cfunctions/cp-unix-env/) - [_CP_unlock](https://d3codex.com/cfunctions/cp-unlock/) - [_CP_unlock_all](https://d3codex.com/cfunctions/cp-unlock-all/) - [_CP_weof](https://d3codex.com/cfunctions/cp-weof/) - [_CP_write](https://d3codex.com/cfunctions/cp-write/) - [_CP_writefields](https://d3codex.com/cfunctions/cp-writefields/) - [_CP_writet](https://d3codex.com/cfunctions/cp-writet/) - [_CP_writev](https://d3codex.com/cfunctions/cp-writev/) - [_CP_xtd](https://d3codex.com/cfunctions/cp-xtd/) --- Source: https://d3codex.com/cfunctions/c-programming-language-c-functions-list/ - part of the D3Codex reference.