--- name: "explain_tcsetattr" section: "3" platform: "linux" package: "libexplain-dev" version: "1.4.D001-16" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/explain_tcsetattr" --- # explain\_tcsetattr(3) explain tcsetattr(3) errors ## NAME explain\_tcsetattr - explain [*tcsetattr*(3)](/tcsetattr/3.md) errors ## SYNOPSIS \#include \ const char \*explain\_tcsetattr(int fildes, int options, const struct termios \*data);\ const char \*explain\_errno\_tcsetattr(int errnum, int fildes, int options, const struct termios \*data);\ void explain\_message\_tcsetattr(char \*message, int message\_size, int fildes, int options, const struct termios \*data);\ void explain\_message\_errno\_tcsetattr(char \*message, int message\_size, int errnum, int fildes, int options, const struct termios \*data); ## DESCRIPTION These functions may be used to obtain explanations for errors returned by the [*tcsetattr*(3)](/tcsetattr/3.md) system call. ### explain\_tcsetattr const char \*explain\_tcsetattr(int fildes, int options, const struct termios \*data); The **explain\_tcsetattr** function is used to obtain an explanation of an error returned by the [*tcsetattr*(3)](/tcsetattr/3.md) system call. The least the message will contain is the value of `strerror(errno)`, but usually it will do much better, and indicate the underlying cause in more detail. The *errno* global variable will be used to obtain the error value to be decoded. - *fildes* The original fildes, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - *options* The original options, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - *data* The original data, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - Returns: The message explaining the error. This message buffer is shared by all libexplain functions which do not supply a buffer in their argument list. This will be overwritten by the next call to any libexplain function which shares this buffer, including other threads. **Note:** This function is **not** thread safe, because it shares a return buffer across all threads, and many other functions in this library. **Example:** This function is intended to be used in a fashion similar to the following example: `if (tcsetattr(fildes, options, data) < 0)` ``` { ``` `fprintf(stderr, "%s\n", explain_tcsetattr(fildes, options, data));` ``` exit(EXIT_FAILURE); } ``` The above code example is available pre‐packaged as the [*explain\_tcsetattr\_or\_die*(3)](/explain_tcsetattr_or_die/3.md) function. ### explain\_errno\_tcsetattr const char \*explain\_errno\_tcsetattr(int errnum, int fildes, int options, const struct termios \*data); The **explain\_errno\_tcsetattr** function is used to obtain an explanation of an error returned by the [*tcsetattr*(3)](/tcsetattr/3.md) system call. The least the message will contain is the value of `strerror(errno)`, but usually it will do much better, and indicate the underlying cause in more detail. - *errnum* The error value to be decoded, usually obtained from the *errno* global variable just before this function is called. This is necessary if you need to call **any** code between the system call to be explained and this function, because many libc functions will alter the value of *errno*. - *fildes* The original fildes, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - *options* The original options, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - *data* The original data, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - Returns: The message explaining the error. This message buffer is shared by all libexplain functions which do not supply a buffer in their argument list. This will be overwritten by the next call to any libexplain function which shares this buffer, including other threads. **Note:** This function is **not** thread safe, because it shares a return buffer across all threads, and many other functions in this library. **Example:** This function is intended to be used in a fashion similar to the following example: `if (tcsetattr(fildes, options, data) < 0)` ``` { int err = errno; ``` `fprintf(stderr, "%s\n", explain_errno_tcsetattr(err, fildes, options,` `data));` ``` exit(EXIT_FAILURE); } ``` The above code example is available pre‐packaged as the [*explain\_tcsetattr\_or\_die*(3)](/explain_tcsetattr_or_die/3.md) function. ### explain\_message\_tcsetattr void explain\_message\_tcsetattr(char \*message, int message\_size, int fildes, int options, const struct termios \*data); The **explain\_message\_tcsetattr** function is used to obtain an explanation of an error returned by the [*tcsetattr*(3)](/tcsetattr/3.md) system call. The least the message will contain is the value of `strerror(errno)`, but usually it will do much better, and indicate the underlying cause in more detail. The *errno* global variable will be used to obtain the error value to be decoded. - *message* The location in which to store the returned message. If a suitable message return buffer is supplied, this function is thread safe. - *message\_size* The size in bytes of the location in which to store the returned message. - *fildes* The original fildes, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - *options* The original options, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - *data* The original data, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. **Example:** This function is intended to be used in a fashion similar to the following example: `if (tcsetattr(fildes, options, data) < 0)` ``` { char message[3000]; ``` `explain_message_tcsetattr(message, sizeof(message), fildes, options,` `data);` ``` fprintf(stderr, "%s\n", message); exit(EXIT_FAILURE); } ``` The above code example is available pre‐packaged as the [*explain\_tcsetattr\_or\_die*(3)](/explain_tcsetattr_or_die/3.md) function. ### explain\_message\_errno\_tcsetattr void explain\_message\_errno\_tcsetattr(char \*message, int message\_size, int errnum, int fildes, int options, const struct termios \*data); The **explain\_message\_errno\_tcsetattr** function is used to obtain an explanation of an error returned by the [*tcsetattr*(3)](/tcsetattr/3.md) system call. The least the message will contain is the value of `strerror(errno)`, but usually it will do much better, and indicate the underlying cause in more detail. - *message* The location in which to store the returned message. If a suitable message return buffer is supplied, this function is thread safe. - *message\_size* The size in bytes of the location in which to store the returned message. - *errnum* The error value to be decoded, usually obtained from the *errno* global variable just before this function is called. This is necessary if you need to call **any** code between the system call to be explained and this function, because many libc functions will alter the value of *errno*. - *fildes* The original fildes, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - *options* The original options, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. - *data* The original data, exactly as passed to the [*tcsetattr*(3)](/tcsetattr/3.md) system call. **Example:** This function is intended to be used in a fashion similar to the following example: `if (tcsetattr(fildes, options, data) < 0)` ``` { int err = errno; char message[3000]; ``` `explain_message_errno_tcsetattr(message, sizeof(message), err, fildes,` `options, data);` ``` fprintf(stderr, "%s\n", message); exit(EXIT_FAILURE); } ``` The above code example is available pre‐packaged as the [*explain\_tcsetattr\_or\_die*(3)](/explain_tcsetattr_or_die/3.md) function. ## SEE ALSO - [*tcsetattr*(3)](/tcsetattr/3.md) set terminal attributes - [*explain\_tcsetattr\_or\_die*(3)](/explain_tcsetattr_or_die/3.md) set terminal attributes and report errors ## COPYRIGHT libexplain version 1.4\ Copyright (C) 2009 Peter Miller